Interaction between common variants of FTO and MC4R is associated with risk of PCOS

Genetic variants of metabolism and inflammatory pathways, and PCOS risk -Systematic review, meta-analysis, and in-silico analysis

IMPORTANCE

Identification of genetic risk factors for PCOS susceptibility.

OBJECTIVE

To identify genetic risk variants of the genes involved in metabolic or inflammatory pathways.

DATA SOURCES

Relevant literature was identified and extracted from PubMed, Central Cochrane Library, Google Scholar, and Science Direct by using a set of keywords related to pre-determined genes up to 06 May 2023. Study selection and synthesis: PRISMA guidelines were followed to design the protocol which is registered in PROSPERO (CRD42023422501). Pooled odds ratio (OR) and 95% confidence interval (95% CI) for different gene variants were calculated under different genetic models (dominant model, recessive model, additive model, and allele model) by using Review Manager software 4.2.

MAIN OUTCOMES

Metabolic genetic variants FTO rs9939609, IL-6 rs1800795 and CAPN10 rs3842570, rs2975760, and RAB5B rs705702 are associated with PCOS risk.

RESULTS

Forty-four relevant articles have been identified for genes involved in metabolic (n = 23) or inflammatory pathways (n = 21). There is a significant association (p < 0.05) of IL-6 rs1800795 and FTO rs9939609 with increased risk.CAPN10 rs2975760 Ins allele is suggested as a protective factor among only the non-Asian population. Also, a significant association of CAPN10 rs2975760 and RAB5B rs705702 with increased risk among the Asian population is suggested. However, no significant association could be found between CAPN10 rs3792267, rs5030952, and SUMO1P1 rs2272046, and the risk of PCOS in any of the subpopulations analysed. In silico analysis suggests the deleterious effect of IL-6 rs1800795.

CONCLUSION

and relevance: The study suggests the role of various genetic variants for genetic predisposition to PCOS among different subpopulations.

FTO: a critical role in obesity and obesity-related diseases

In recent years, obesity is a growing pandemic in the world and has likely contributed to increasing the incidence of obesity-related diseases. Fat mass and obesity-associated gene (FTO) is the first gene discovered which has a close connection with fat. Recent studies suggested that FTO gene has played an important role in the molecular mechanisms of many diseases. Obesity is considered to be a hereditary disease and can evoke many kinds of diseases, including polycystic ovary syndrome (PCOS), type 2 diabetes mellitus (T2DM), cancer, etc., whose exact possible molecular mechanisms responsible for the effect of FTO on obesity and obesity-related diseases remain largely unknown. In this review, we comprehensively discuss the correlation between FTO gene and obesity, cancer, PCOS, T2DM, as well as the molecular mechanism involved in these diseases.

MC4R in Central and Peripheral Systems

Obesity has emerged as a critical and urgent health burden during the current global pandemic. Among multiple genetic causes, melanocortin receptor-4 (MC4R), involved in food intake and energy metabolism regulation through various signaling pathways, has been reported to be the lead genetic factor in severe and early onset obesity and hyperphagia disorders. Most previous studies have illustrated the roles of MC4R signaling in energy intake versus expenditure in the central system, while some evidence indicates that MC4R is also expressed in peripheral systems, such as the gut and endocrine organs. However, its physiopathological function remains poorly defined. This review aims to depict the central and peripheral roles of MC4R in energy metabolism and endocrine hormone homeostasis, the diversity of phenotypes, biased downstream signaling caused by distinct MC4R mutations, and current drug development targeting the receptor.

Differential Association of FTO Gene variants and Haplotypes with the Susceptibility to Polycystic Ovary Syndrome According To Obesity in Women with PCOS

We explored the relation between FTO single gene variants (rs1861868, rs9939973, rs1421085, rs1121980, rs17817449, rs8050136, rs9939609, rs9930506, and rs8044769) and polycystic ovary syndrome (PCOS), in particular, according to the obesity status. This retrospective population-based case-control study involved women with PCOS (583) and 713 eumenorrheic control women; genotyping was done by real-time PCR. Significantly higher minor allele frequency (MAF) of rs9939973, rs17817449, rs9939609, and rs9930506 and lower MAF of rs1121980 were seen in PCOS cases. Lower risk of PCOS was associated with rs1121980 and rs8050136 heterozygous and minor allele-homozygous genotypes, while an elevated risk of PCOS was seen with minor allele-homozygous rs9939973, rs17817449, and r9939609 heterozygous and genotypes and minor allele-homozygous rs9930506 and rs8044769 genotype. While none of the tested FTO SNPs variants was associated with PCOS in normal body weight/lean subjects, rs9939973, rs9939609, and rs9930506 were negatively associated with PCOS in overweight subjects. In comparison, rs1861868 was negatively, while rs8044769 was positively associated with PCOS in obese subjects. Haplotype analysis identified haplotypes GACCTCTAT, AACCTCTAT, AACCTATAT and AGTTGCAGC, and GACCTCTAC to be positively associated with PCOS, while haplotypes GGTTGAAGC, GACCTATAT, GGTTGCAGC, and GATCTATAT were negatively associated with PCOS. Apart from GGTTGAAGC, these haplotypes remained associated with altered risk of PCOS after adjusting for covariates. In addition to rs17817449, rs9939609, rs9930506, and rs1121980, this study is the first to demonstrate association of rs9939973 and rs8044769 with altered risk of PCOS and the first to confirm the BMI dependency on the association of FTO variants with PCOS. This underscores the role of FTO gene variants as predisposing factors of PCOS.

Causality of anthropometric markers associated with polycystic ovarian syndrome: Findings of a Mendelian randomization study

Introduction

Using body mass index (BMI) as a proxy, previous Mendelian randomization (MR) studies found total causal effects of general obesity on polycystic ovarian syndrome (PCOS). Hitherto, total and direct causal effects of general- and central obesity on PCOS have not been comprehensively analyzed.

Objectives

To investigate the causality of central- and general obesity on PCOS using surrogate anthropometric markers.

Methods

Summary GWAS data of female-only, large-sample cohorts of European ancestry were retrieved for anthropometric markers of central obesity (waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR)) and general obesity (BMI and its constituent variables–weight and height), from the IEU Open GWAS Project. As the outcome, we acquired summary data from a large-sample GWAS (118870 samples; 642 cases and 118228 controls) within the FinnGen cohort. Total causal effects were assessed via univariable two-sample Mendelian randomization (2SMR). Genetic architectures underlying causal associations were explored. Direct causal effects were analyzed by multivariable MR modelling.

Results

Instrumental variables demonstrated no weak instrument bias (F > 10). Four anthropometric exposures, namely, weight (2.69–77.05), BMI (OR: 2.90–4.06), WC (OR: 6.22–20.27), and HC (OR: 6.22–20.27) demonstrated total causal effects as per univariable 2SMR models. We uncovered shared and non-shared genetic architectures underlying causal associations. Direct causal effects of WC and HC on PCOS were revealed by two multivariable MR models containing exclusively the anthropometric markers of central obesity. Other multivariable MR models containing anthropometric markers of both central- and general obesity showed no direct causal effects on PCOS.

Conclusions

Both and general- and central obesity yield total causal effects on PCOS. Findings also indicated potential direct causal effects of normal weight-central obesity and more complex causal mechanisms when both central- and general obesity are present. Results underscore the importance of addressing both central- and general obesity for optimizing PCOS care.

Association of FTO gene variant rs9939609 with hyperandrogenemia and fasting glucose levels in South Indian women with polycystic ovarian syndrome

Background

Polycystic ovary syndrome (PCOS) is a common endocrine–metabolic disorder due to genetic and environmental factors. Genetic variants located in intron 1 of Fat mass and obesity-associated (FTO) gene are associated with increased risk of obesity and metabolic disorders. This study aims to investigate the association of common FTO polymorphism rs9939609 in South Indian women with PCOS to assess its association with metabolic and endocrine parameters. FTO genotyping was done on 100 PCOS patients and 70 controls by Sanger sequencing.

Results

The distribution of rs9939609 was observed between groups (28% TT, 57% TA, and 15% AA for PCOS and 37.1% TT, 51.4% TA, and 11.4% AA for the controls). In the PCOS group, across the carriers of different genotypes, a significant association was found between body mass index (BMI), fasting glucose levels, and testosterone with the presence of at least one risk allele of FTO rs9939609. Logistic regression analysis showed the association of fasting glucose levels and testosterone (OR 1.30 [1.03–1.63] and OR 5.83 [1.61–21.11], respectively) with FTO rs9939609.

Conclusions

Our findings indicated that FTO SNP rs9939609 was not associated with PCOS, but suggested a significant association of rs9939609 with hyperandrogenemia, fasting glucose levels, and BMI in South Indian women with PCOS.

Association of FTO gene variants rs9939609 and rs1421085 with polycystic ovary syndrome

Background

Polycystic ovary syndrome (PCOS) is among the most common complex genetic endocrinopathy, and its etiology and pathophysiology remain controversial. FTO is a large highly polymorphic gene and was coined as the first locus associated with adiposity. The association of the intronic variant FTO rs9939609 or FTO rs1421085 with PCOS has been controversial and unclear, mainly due to ethnic differences among populations. The present study aims to investigate the association of FTO rs9939609 or FTO rs1421085 polymorphisms with PCOS in Saudi Arabian women.

Results

A total of 98 PCOS patients and 99 healthy females were included in this study. PCR and genotyping (TaqMan®SNP Genotyping Assay) were employed. For FTO rs9939609, the genotype TA and the recessive model (TA + AA) in PCOS patients were significantly different compared with control subjects (p = 0.008 and p = 0.007, respectively). The allele frequency of the FTO rs9939609 gene variant was associated significantly (p = 0.027) with PCOS, suggesting that the A allele is a risk factor for PCOS susceptibility. However, for the FTO rs1421085 variant, the genotype and allele distributions did not differ significantly between PCOS patients and controls (p > 0.05).

Conclusions

This is the first report to study the association of FTO rs9939609 and FTO rs1421085 with PCOS in Saudi women. Results suggest that the FTO rs9939609 gene variant could be a genetic predisposing factor for PCOS Saudi women.

Genomic correlation, shared loci, and causal relationship between obesity and polycystic ovary syndrome: a large-scale genome-wide cross-trait analysis

BACKGROUND

The comorbidity between polycystic ovary syndrome (PCOS) and obesity has long been observed in clinical settings, but their shared genetic basis remains unclear.

METHODS

Leveraging summary statistics of large-scale GWAS(s) conducted in European-ancestry populations on body mass index (adult BMI, Nfemale=434,794; childhood BMI, N=39,620), waist-to-hip ratio (WHR, Nfemale=381,152), WHR adjusted for BMI (WHRadjBMI, Nfemale=379,501), and PCOS (Ncase=10,074, Ncontrol=103,164), we performed a large-scale genome-wide cross-trait analysis to quantify overall and local genetic correlation, to identify shared loci, and to infer causal relationship.

RESULTS

We found positive genetic correlations between PCOS and adult BMI (rg=0.47, P=2.19×10-16), childhood BMI (rg=0.31, P=6.72×10-5), and WHR (rg=0.32, P=1.34×10-10), all withstanding Bonferroni correction. A suggestive significant genetic correlation was found between PCOS and WHRadjBMI (rg=0.09, P=0.04). Partitioning the whole genome into 1703 nearly independent regions, we observed a significant local genetic correlation for adult BMI and PCOS at chromosome 18: 57630483-59020751. We identified 16 shared loci underlying PCOS and obesity-related traits via cross-trait meta-analysis including 9 loci shared between BMI and PCOS (adult BMI and PCOS: 5 loci; childhood BMI and PCOS: 4 loci), 6 loci shared between WHR and PCOS, and 5 loci shared between WHRadjBMI and PCOS. Mendelian randomization (MR) supported the causal roles of both adult BMI (OR=2.92, 95% CI=2.33-3.67) and childhood BMI (OR=2.76, 95% CI=2.09-3.66) in PCOS, but not WHR (OR=1.19, 95% CI=0.93-1.52) or WHRadjBMI (OR=1.03, 95% CI=0.87-1.22). Genetic predisposition to PCOS did not seem to influence the risk of obesity-related traits.

CONCLUSIONS

Our cross-trait analysis suggests a shared genetic basis underlying obesity and PCOS and provides novel insights into the biological mechanisms underlying these complex traits. Our work informs public health intervention by confirming the important role of weight management in PCOS prevention.

Polycystic ovary syndrome is linked with the fat mass obesity (FTO) gene variants rs17817449 and rs1421085 in western Saudi Arabia

Polycystic ovary syndrome (PCOS) is characterised by infertility, obesity, insulin resistance and clinical and/or biochemical signs of hyperandrogenism. Obesity is known to be correlated with PCOS causing ovulatory dysfunction and hormone imbalances. Moreover, fat mass and the obesity gene (FTO) were linked with obesity and PCOS. Therefore, it is of interest to determine the genotype and allele frequency for three FTO variants - rs17817449 (G/T), rs1421085 (C/T) and rs8050136 (A/C) -in western Saudi population. 95 PCOS patients and 94 controls were recruited for this study. The genetic variants were assayed using real-time polymerase chain reaction using TaqMan genotyping assays. The chi-squared test was applied to investigate the difference between single nucleotide polymorphisms on PCOS and control subjects, and binary logistic regression was used to determine the association of FTO variants with PCOS symptoms. Variants rs17817449 and rs1421085 were significantly linked with PCOS susceptibility in the study population. Rs17817449 and rs8050136 were significantly associated with hair loss in the PCOS group. Furthermore, rs1421085 and rs8050136 were associated with a high body mass index (BMI>30 kg/m2). Risk alleles in our population associated with hair loss and elevated BMI in women with PCOS were homozygous C for rs8050136. This data will help in defining the genetic predisposition of PCOS among women in western Saudi Arabia.

Transmission of polycystic ovary syndrome susceptibility single-nucleotide polymorphisms and their association with phenotype changes in offspring

STUDY QUESTION

Does the inheritance of polycystic ovary syndrome (PCOS) susceptibility single-nucleotide polymorphism affect the phenotype of offspring?

SUMMARY ANSWER

Male offspring who inherit PCOS-related genetic variations from PCOS mothers were more susceptible to developing the metabolic abnormality in their later life.

WHAT IS KNOWN ALREADY

Genetic factors are considered the major etiology of PCOS. Previous studies have highlighted that offspring of women with PCOS had an increased risk of the same disease or PCOS-like symptoms.

STUDY DESIGN, SIZE, DURATION

The study involved 172 children born to women with PCOS and 529 children born to non-PCOS women. All offspring were conceived by assisted reproductive technologies.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The offspring ranged from 1 to 8 years old. Metabolic phenotype analyses were performed in offspring aged from 2 to 8 (N = 619). Sanger sequencing, TaqMan and Sequenom MassARRAY were used to sequence the samples.

MAIN RESULTS AND THE ROLE OF CHANCE

In male offspring, the fasting insulin (FINS) (P = 0.037) homeostasis model assessment of insulin resistance (HOMA-IR) (P = 0.038) and the homeostasis model assessment of pancreatic beta-cell function (HOMA-β) (P = 0.038) levels were higher in offspring of PCOS mothers compared to controls. In female offspring, PCOS offspring had a significantly higher anti-Müllerian hormone levels (P = 0.001) compared to those from control mothers. In male offspring of PCOS mothers, subjects with a T allele at rs2349415 in the gene FSHR had higher FINS (P = 0.023), HOMA-IR (P = 0.030) and HOMA-β levels (P = 0.013) than those in the homozygous CC group. The same increased trend in FINS, HOMA-IR and HOMA-β levels could be found in the CC and TC group in rs2268361 located in gene FSHR compared to the TT group (P = 0.029, P = 0.030, P = 0.046, respectively). As for rs10818854 in the DENND1A gene, the AA and AG group had a higher FINS (P = 0.037) and HOMA-β (P = 0.008) levels than the homozygous CC group.

LIMITATIONS, REASONS FOR CAUTION

Firstly, the offspring may be too young to see any phenotype changes. Secondly, this study only analyzed the differences of genotype frequency using the dominant model instead of all three models due to the limited sample size of the homozygous model. The results, therefore, should be replicated and performed in a larger sample size population. Thirdly, environmental impacts cannot be ruled out.

WIDER IMPLICATIONS OF THE FINDINGS

The findings presented in this thesis add to our understanding the changes in offspring born to PCOS women and remind us to consider early intervention to avoid more severe effects.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the National Key Research and Development Program of China 2017YFC1001000 (to Z.-J.C.), the National Natural Science Foundation of China 81430029 (to Z.-J.C.), 81622021 and 31571548 (to H.Z.), the National Natural Science Foundation of Shandong Province JQ201816 (to H.Z.) and Shandong Provincial Key Research and Development Program 2017G006036 (to L.-L.C.) and 2018YFJH0504 (to Z.-J.C.). There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Cryptotanshinone alleviates polycystic ovary syndrome in rats by regulating the HMGB1/TLR4/NF‑κB signaling pathway

Cryptotanshinone (CRY) has been demonstrated to reverse reproductive disorders. However, whether CRY is effective in the treatment of polycystic ovary syndrome (PCOS) remains unknown. The aim of the present study was to evaluate the therapeutic potential of CRY in PCOS. A rat model of PCOS was established by daily injection of human chorionic gonadotropin and insulin for 22 days. Total body weight and ovarian weight, as well as the levels of luteinizing hormone (LH) and the LH to follicle-stimulating hormone (FSH) ratio (LH/FSH) significantly increased in rats with PCOS, compared with controls. Moreover, the levels of testosterone (T), tumor necrosis factor (TNF)-α and high-mobility group box 1 protein (HMGB1) also increased. However, CRY treatment attenuated the increase in body weight, ovarian weight, LH, LH/FSH ratio, T, TNF-α and HMGB1 levels, compared with the PCOS group. Treatment with CRY also reduced NF-κB/p65, HMGB1 and toll-like receptor (TLR)4 mRNA and protein expression levels in the ovarian tissue and granulosa cells, both in vitro and in vivo. Thus, CRY significantly mitigated the changes in body weight, ovary weight, hormone levels and inflammatory factor levels observed in rats with PCOS. Thus, CRY protects against PCOS-induced damage of ovarian tissue, possibly through a regulatory pathway involving HMGB1, TLR4 and NF-κB.

Weighing the Impact of Diet and Lifestyle on Female Reproductive Function

BACKGROUND

In the last years, several scientific societies and expert groups focused on the role played by nutritional factors, lifestyle and excess of body fat in interfering with female reproduction and fertility. In many studies a confounding factor is represented by polycystic ovary syndrome (PCOS) which is one of the major causes of infertility where genetic and family history are certainly playing a role, together with lifestyle and nutritional factors.

METHODS

In an attempt to define "the optimal fertility diet", we consider the role played by Mediterranean lifestyle and some macronutrients (animal and vegetable proteins) on ovulatory disorders and female fertility also considering some new visions derived from randomized trials of lifestyle programs in obese infertile women asking for in vitro fertilization or alternative assisted reproduction technologies.

RESULTS

Several reports are in favor of an increased consumption of either proteins or low-glycemic index carbohydrates to improve ovulatory disorders and female fertility. In studies concerning infertile women undergoing assisted reproduction, either structured exercise sessions and dietary intervention programs seem to be effective in improving menstrual cycles and fertility as demonstrated by the increased rate of natural conceptions.

CONCLUSION

The findings of this review confirm the important impact of Mediterranean diet and lifestyle in preserving and improving fertility. However, epigenetic factors are very important in determining fertility rate, but genetic background and ethnicity are also playing crucial roles.

Pathophysiologic mechanisms of obesity- and chronic inflammation-related genes in etiology of polycystic ovary syndrome

OBJECTIVES

One of the common heterogeneous reproductive disorders in women of childbearing age is polycystic ovary syndrome (PCOS). It is characterized by lack of fertility due to anovulatory cycles, hyperandrogenemia, polycystic ovaries, hyperinsulinemia, and obesity. Both reproductive anomalies and metabolic disorders are involved in PCOS pathology. Although the role of increased levels of androgens in initiation of PCOS is almost proven, mechanisms of PCOS pathophysiology are not clear. Here we discuss roles of altered metabolic conditions, obesity, and chronic inflammation in PCOS pathophysiology.

MATERIALS AND METHODS

In this review, we attempted to identify genes related to obesity and chronic inflammation aspects of PCOS and their physiological functions to explain the pathways that are regulated by these genes and can be a prominent function in PCOS predisposition. For this purpose, published articles and reviews dealing with genetic evaluation of PCOS in women in peer-reviewed journals in PubMed and Google Scholar databases were included in this review.

RESULTS

Obesity and chronic inflammation are not prominent diagnostic features of PCOS, but they play an important role in exacerbating metabolic and hyperandrogenic states. ADIPOQ, FTO TGFβ, and DENND1A as the main obesity- and chronic inflammation-related genes have roles in PCOS pathophysiology.

CONCLUSION

It seems that genes related to obesity pathology in genomic research association, are related to metabolic aspects and body mass index in PCOS patients. Genomes have roles in chronic inflammation, followed by obesity, in the pathogenesis of PCOS.

Phenotype and genotype of polycystic ovary syndrome in Asia: Ethnic differences

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in reproductive-aged women, and ethnic diversity has been reported in its manifestation. This review addressed phenotype and genetic studies in Asian women with PCOS. Generally, East Asians are less hirsute, and the hirsutism score cutoff is lower than the Caucasian counterpart. It is not clear whether there are any significant differences in the prevalence or severity of irregular menstruation (IM) or characteristics of polycystic ovary (PCO) across ethnicities. Interestingly, the IM/PCO subgroup is a relatively common phenotype in East Asian patients but not in Caucasian patients. The prevalence of insulin resistance in PCOS patients varies depending on the index used and the cutoff, but women with PCOS showed a higher degree of insulin resistance than those of controls across ethnicities. Lower body mass index (BMI) and lower prevalence of metabolic syndrome were reported in East Asian patients, but despite lower BMI, a comparative study reported that Asian women with PCOS were more likely to have diabetes compared with Caucasian patients, suggesting they also have metabolic complications. Unlike East Asian patients, South Asian patients showed an increased degree of hirsutism, early onset of symptoms, and severe insulin resistance and metabolic risks compared with Caucasians. Genetic components play important roles in the pathogenesis of PCOS, and genome-wide association studies of PCOS suggest that similar genetic risk factors exist between Asian and Caucasian patients. Continuous comparative studies are needed to standardize the diagnosis and management of PCOS across different ethnicities.

MC4R variants rs12970134 and rs17782313 are associated with obese polycystic ovary syndrome patients in the Western region of Saudi Arabia

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder causing infertility in reproductive-age women. The cause of PCOS is not fully understood but it is thought to be influenced by environmental and genetic factors. Obesity is greatly related to PCOS and its reduction is one of the major aims in treating PCOS. Melanocortin 4 receptor (MC4R) gene polymorphisms were detected to be associated with different levels of obesity. Therefore, we aimed to determine the genotype and allele frequency of MC4R variants rs12970134 (A/G) and rs17782313 (C/T) in PCOS and investigate their association with PCOS and its clinical variables.

METHODS

A case-control study was conducted on 189 women, consisting of 95 PCOS cases and 94 controls. Genotyping was performed by real-time polymerase chain reaction (PCR) using TaqMan™ Genotyping assays. Quantitative data were presented as (median ± interquartile range (IQR) whereas qualitative data were presented as frequencies. The chi-squared test was used to observe the difference between SNPs within the study groups (PCOS and control subjects). Multinomial logistic regression was used to test the risk of obesity and development of PCOS considering p < 0.05 is statistically significant.

RESULTS

Rs12970134 and rs17782313 are significantly associated with body mass index (BMI, kg/m², p < 0.0001) in PCOS women but not associated with PCOS itself. Risk alleles in our population are A in rs12970134 and C in rs17782313 that are associated with high BMI (> 30 kg/m²) in obese women with PCOS (OR = 1.348, p = 0.002 and OR = 1.364, p = 0.002 respectively) in the homozygous state. In addition, we found that the other genotypes for non-obese PCOS group, AG/GG for rs12970134 and CT/TT for rs17782313, are associated with hirsutism, loss of hair, hyperandrogenism and anti-Müllerian hormone in PCOS.

CONCLUSIONS

These findings demonstrate that MC4R single nucleotide polymorphisms, rs12970134 and rs17782313, are correlated with elevated BMI in PCOS but are not causative factors for PCOS among women in the western region of Saudi Arabia. Moreover, the reverse genotypes are associated with major clinical variants in non-obese (< 30 kg/m²) PCOS patients may demonstrate a poor prognosis for this group.

Melanocortin 3 receptor gene polymorphism is associated with polycystic ovary syndrome in Turkish population

Polycystic ovary syndrome (PCOS) is a frequent complex disorder with an ill-defined etiology. Genetic factors seem rather effective at the occurrence of the disease, however, the evidence of established various studies results are unsatisfied. We aimed to make a contribution to the genetic baseline of the disease by investigating melanocortin 3 receptor gene polymorphism in affected patients. 101 PCOS patients and 162 age-matched healthy volunteered control subjects recruited to the study. PCOS patients classified according to their BMI class and insulin resistance situation. Anthropometric measurements, physical examination results, laboratory findings, and hormone levels were recorded for each participant and analysis of two SNPs on the MC3R gene; rs3746619 and rs3827103 were performed. Although no significant difference was observed in rs3827103 polymorphism between PCOS patients and controls; rs3746619 polymorphism was determined associated with PCOS in the heritage of dominant (AA + AC) and co-dominant (AA) genotypes. Two polymorphisms did not found related to obesity and insulin resistance in PCOS subgroups analysis. MC3R gene rs 3746619 polymorphism was found associated with PCOS in the Turkish population and may make a contribution to the genetic baseline of the disease.

Enhancement of Melanocortin-4 Receptor (MC4R) and Constancy of Kiss1 mRNAs Expression in the Hypothalamic Arcuate Nucleus in a Model of Polycystic Ovary Syndrome Rat

Background:

Hypothalamic Melanocortin-4Receptor (MC4R) and kiss1/kisspeptin systems play roles in reproductive processes. This study was conducted to evaluate changes in MC4R and kiss1 genes expression in the arcuate nucleus (ARC) of the hypothalamus and its relationship with polycystic ovary syndrome (PCOS) in rats.

Materials and Methods:

In the current experimental study, 24 female rats were randomly and equally allocated into nulliparous and primiparous groups and then were divided into two subgroups of PCOS and control. PCOS was induced by exposure to continuous light. Sex-related hormones were evaluated by radioimmunoassay or immunoradiometric assay. Expressions of MC4R and kiss1 gene in the ARC of the hypothalamus of the rats were evaluated by real-time PCR. Histomorphometric alterations of ovaries were compared between groups.

Results:

Number of tertiary follicles and their size and number of atretic follicles in the PCOS subgroups were more than those in the controls (P<0.05) whereas the number of secondary follicles and corpus luteum in the PCOS subgroups were lower than those in the controls (P<0.05). Antrum and total diameters of tertiary follicles in the PCOS subgroups were greater and granulosa layer diameter was lower than those in the controls (P<0.05). The MC4R mRNA expression in the PCOS subgroups was 6.5-fold in nulliparous and 3.5-fold in primiparous groups more than their controls’ pairs (P<0.05). However, parity did not affect the expression of MC4R gene (P>0.05). The kiss1 mRNA expression in the PCOS and control subgroups was not significantly different (P>0.05).

Conclusion:

Overexpression of MC4R gene after PCOS induction in the ARC of the hypothalamus may link to metabolic disorders of induced PCOS in the rats. However, alteration in the kiss1 mRNA expression after PCOS induction was not observed in the rats.

Chinese Herbal Medicine for the Optimal Management of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a complex heterogeneous disorder characterized by androgen excess and ovulatory dysfunction; it is now known to be closely linked to metabolic syndrome. Recent research suggests that insulin resistance plays an important role in the pathogenesis of PCOS which may lead to the excessive production of androgens by ovarian theca cells. Currently there is no single drug that can treat both the reproductive and metabolic complications of the disorder. Existing pharmaceutical agents such as hormonal therapies have been associated with side effects and are not appropriate for PCOS women with infertility. Additionally, insulin sensitizing agents useful for treating the metabolic abnormalities in PCOS have limited efficacy for treating reproductive aspects of the disorder. Chinese herbal medicines have a long history of treating gynaecological problems and infertility and therefore may be a novel approach to the treatment of PCOS. Current research demonstrates that the compounds isolated from herbs have shown beneficial effects for PCOS and when combined in an herbal formula can target both reproductive and metabolic defects simultaneously. Therefore, further investigation into Chinese herbal medicine in the treatment of PCOS is warranted.

Fat Mass and Obesity Associated Gene Polymorphism and the Risk of Polycystic Ovary Syndrome: A Meta-analysis

BACKGROUND

We aimed to elucidate the association between fat mass and obesity associated gene (FTO) polymorphism and the risk of polycystic ovary syndrome (PCOS) by meta-analysis.

METHODS

We searched PubMed and Embase databases to find the relevant studies. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were used for pooled analysis. Statistical analyses were carried out by using R 3.12 software. Heterogeneity was assessed using I ² and Q statistics. I ² >50% or P<0.05 was considered as heterogeneity statistically, and random effects model was used for pooled analysis. Otherwise, fixed-effect model was used.

RESULTS

Twelve eligible studies that published from 2008 to 2015 were included in this meta-analysis. The pooled analyses showed that rs9939609 polymorphism of FTO gene was significantly associated with risk of PCOS under A vs. T, AT vs. TT, AA vs. TT, AA vs. AT+TT and AA+AT vs. TT genetic models. However, for rs8050136 and rs1421085, significant association was only found under recessive genetic model.

CONCLUSION

rs9939609 variation of FTO gene is significantly associated with risk of PCOS. However, the association between rs8050136, rs1421085, and PCOS is still unclear and needs further confirmation.

Association of common variants of FTO in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common and complex multisystemic genetic disease. Previous genome-wide association study (GWAS) of PCOS has found several potentially causative single nucleotide polymorphisms (SNPs) in Han Chinese population. The goal of present investigation was to assess the potential association between rs1121980, rs1421085, rs1558902, rs8050136 SNPs and PCOS. In order to make a better elucidation of this disease, further investigations of association between SNPs susceptibility and PCOS become necessary.

METHODS

In the present study, we enrolled 212 patients with PCOS and 198 control subjects. Four polymorphisms of FTO gene (rs1121980, rs1421085, rs1558902, rs8050136) were genotyped by Taqman-MGB method, and their relationship with PCOS was speculated.

RESULTS

The allele frequency has no significant difference between the PCOS group and the controls. Genotype frequencies of the four SNPs in the additive, dominant and recessive models showed no significant difference between PCOS cases and controls.

CONCLUSIONS

Our results demonstrate that FTO gene has little association in PCOS development.