CYP19 gene variants affect the assisted reproduction outcome of women with polycystic ovary syndrome

Selenium Nanoparticles Modulate Steroidogenesis-Related Genes and Improve Ovarian Functions via Regulating Androgen Receptors Expression in Polycystic Ovary Syndrome Rat Model

Polycystic ovary syndrome (PCOS) occurs during the reproductive period in women and is characterized by reproductive, endocrine, and metabolic disorders. Androgen plays a decisive role in its pathogenesis due to the interaction between hyperandrogenism and insulin resistance, which might be improved by selenium nanoparticles (SeNPs). The present study aimed to clarify the effect of SeNPs on androgen synthesis and action in the PCOS model and the resulting effect on ovarian function. Fifty-five 7-week-old female albino rats (90-105 g) were divided equally into five groups: control (C), fed a standard diet for 11 weeks; high-fat diet (HFD) group, fed HFD for 11 weeks; HFD and letrozole (L) (HFD + L), fed HFD for 11 weeks and administrated orally with L, at a daily dose of 1 mg/kg BW, for three weeks from the 7th to 9th week of the trial; HFD + L + 0.1SeNPs and HFD + L + 0.2SeNPs groups, treated the same as HFD + L group and orally gavaged SeNPs at daily doses of 0.1 and 0.2 mg/kg BW, respectively, during the last 14 day of the experiment. Daily determination of estrous cycle was performed, and at the end of the experimental period, BMI, serum glucose, insulin, HOMA-IR, lipid profile, sex hormones, TNF-α, IL6, oxidative stress biomarkers, ovarian mRNA expression of different proteins and enzymes involved in steroidogenesis, pathological examination, and immunohistochemical staining for androgen receptor (AR) were evaluated. Treatment of SeNPs restored estrous cyclicity, decreased BMI, and insulin resistance, improved dyslipidemia, reduced serum testosterone, and improved ovarian histopathology in PCOS rats. Furthermore, the anti-inflammatory and antioxidant impacts of SeNPs were remarkably noticed. Administration of SeNPs decreased androgen synthesis and expression of ovarian AR protein by decreasing the mRNA expression of STAR, Cyp11A1, Cyp17A1, and HSD17B3 and increasing the expression of Cyp19α1. Conclusively, SeNPs decreased androgen synthesis and blocked the vicious circle initiated by excessive androgen secretion via decreased AR expression. Thus, it may effectively treat PCOS cases by eliminating its reproductive, endocrine, and metabolic dysfunctions.

A Review on CYP11A1, CYP17A1, and CYP19A1 Polymorphism Studies: Candidate Susceptibility Genes for Polycystic Ovary Syndrome (PCOS) and Infertility

Polycystic ovary syndrome is a multifactorial condition associated with reproductive and endocrine organs and might cause infertility and metabolic abnormalities in childbearing age. PCOS seems to be a multifactorial disorder resulting from the combination of several genetic and environmental factors. Little research has been conducted to date on the impact of polymorphisms in infertility. We aim to review the appearance of polymorphisms in females of diverse ethnicities and their effect on infertility in the population with polycystic ovary syndrome. There have been numerous reports of the importance of the steroidogenesis pathway and genetic variants in PCOS pathogenesis. The most important genes that play a role in the aetiology of PCOS are CYP11A1, CYP17A1, and CYP19A1. We evaluated the occurrence of polymorphisms in various ethnicities in the CYP11A1, CYP17A1, and CYP19A1 genes and their efficacy on increasing PCOS risk with infertility. Our findings revealed that polymorphisms in various ethnicities are associated with the risk of PCOS with infertility. Although conflicting results regarding CYP11A1, CYP17A1, and CYP19A1 polymorphisms and their influence on PCOS with infertility have been reported in a small number of papers, the authors feel this may be attributable to the sample size and ethnic composition of the examined populations. In conclusion, our study strongly suggests that the CYP11A1, CYP17A1, and CYP19A1 genes might significantly enhance the probability of developing PCOS with infertility.

Black race associated with lower live birth rate in frozen-thawed blastocyst transfer cycles: an analysis of 7,002 Society for Assisted Reproductive Technology frozen-thawed blastocyst transfer cycles

OBJECTIVE

To evaluate if racial/ethnic differences in pregnancy outcomes persisted in frozen-thawed embryo transfer (FET) cycles on a national level.

DESIGN

Retrospective cohort study.

SETTING

Clinic-based data.

PATIENT(S)

A total of 189,000 Society for Assisted Reproductive Technology FET cycles from 2014-2016 were screened, of which 12,000 cycles had available fresh cycle linkage information and ultimately, because of missing data, 7,002 FET cycles were included. Cycles were stratified by race (White, Black, Asian, and Hispanic).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary outcome was live birth rate. Secondary outcomes were implantation rate, clinical pregnancy rate, multiple pregnancy rate, and clinical loss rate (CLR).

RESULT(S)

Live birth rate was significantly lower in the Black vs. White and Asian, but not Hispanic group. Implantation rate was also significantly lower and CLR higher in the Black group compared with all other groups (all P<.01). Black women had a lower risk of live birth (adjusted risk ratio, 0.82; 95% confidence interval [CI], 0.73-0.92) and a higher risk of clinical loss (adjusted risk ratio, 1.59; 95% CI, 1.28-1.99) compared with White women. There was no significant difference between groups in clinical pregnancy rate or multiple pregnancy rate. When the analysis was limited to preimplantation genetic testing FET cycles, there remained a significantly lower implantation rate in the Black group compared with all other groups (all P<.01).

CONCLUSION(S)

Black race remains an independent predictor of reduced live birth rate in FET cycles, likely because of higher CLR.

Molecular characterization, expression profile and transcriptional regulation of the CYP19 gene in goose ovarian follicles

Cytochrome P450 Family 19 (CYP19) is a crucial enzyme to catalyze the conversion of androgens to estrogens. However, the regulatory mechanism of goose CYP19 gene remains poorly understood. The present study attempted to obtain the full-length coding sequence (CDS) and 5'-flanking sequence of CYP19 gene, to investigate its expression and distribution profiles in different sized follicles, and to analyze the transcriptional regulatory mechanism of CYP19 gene in goose. Results showed that its CDS consisted of 1512 nucleotides and the encoded amino acid sequence contained a classical P450 structural domain. Homology analysis showed that there were high homologies of nucleotide and amino acid sequences between goose and other avian species. Its promoter sequence spanned from -1925 bp to the transcription start site (ATG) and several transcriptional factors were predicted in this region. Further analysis from luciferase assay showed that the luciferase activity was the highest spanning from -118 to -1 bp by constructing deletion promoter reporter vector. In addition, result from quantitative real-time polymerase chain reaction indicated that the mRNA level of CYP19 gene were highly expressed in theca layer of the fifth largest follicle, and the cellular location was in the theca externa cells by immunohistochemistry. Taken together, it could be concluded that the transcription activity of CYP19 gene was activated by transcriptional factors in its proximal region of promoter to promote the synthesis of estrogens, regulating the selection of pre-hierarchical into hierarchical follicle in goose.

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

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

The Associations of Androgen-Related Genes CYP21A2 and CYP19A1 with Severe Acne Vulgaris in Patients from Southwest China

Objective

Androgens acting through the androgen receptor play a crucial role in the pathogenesis of acne. This study aimed to identify whether two key genes (CYP21A2 and CYP19A1) involved in the synthesis and metabolism of androgens were associated with Pillsbury III-IV severe acne vulgaris.

Methods

We carried out a standard questionnaire survey about acne and enlisted 600 Pillsbury III-IV severe acne vulgaris patients and 652 healthy controls of Han Chinese descent from Yunnan, China in the study. Twenty-two single nucleotide polymorphisms (SNPs) were genotyped by SNaPshot assay and analyzed for association with severe acne.

Results

There was no significant difference in gender between the two groups (P = 0.085), and the age of the acne case group was significantly lower than that of the control group (P < 0.001). Our results revealed that only two SNPs, rs6474 (p.Arg102Lys) (P = 0.001) and rs6465 (P = 0.025) of the CYP21A2 gene were significantly associated with severe acne among the Han Chinese. When subjects were divided into males and females, significant associations were observed only in male patients with severe acne vulgaris for four variants: CYP21A2 rs6474 (p.Arg102Lys) (P = 0.002); CYP21A2 rs6465 (P = 0.012); CYP19A1 rs8023263 (P = 0.037); and CYP19A1 rs2470152 (P = 0.007). Haplotype analyses showed that the distribution of CYP21A2 haplotypes was significantly associated with male patients, while no association of CYP19A1 haplotypes was observed. The structure of the human CYP21A2 consists of two substrate binding sites and one substrate access channel.

Conclusion

This study shed a light on a potentially important effect of CYP21A2 and CYP19A1 genes in severe acne vulgaris in the Han Chinese, especially for male patients. Future studies using independently verified datasets from a broader geographical spectrum will be valuable in identifying the causal and functional variants responsible for severe acne vulgaris within the CYP19A1 and CYP21A2 genes.

CYP19 gene rs2414096 variant and differential genetic risk of polycystic ovary syndrome: a systematic review and meta-analysis

Previously, many studies investigated the association between CYP19 rs2414096(G > A) and susceptibility to develop PCOS. However, results had been inconsistent. Therefore, our systematic review and meta-analysis aimed to identify the association between CYP19 rs2414096 and PCOS risk. Methods: A systematic literature search was done from database PubMed, Google Scholar, Science Direct, and Cochrane Library up to July 15 2020 and statistical analysis was performed by RevMan5.3. Results: A total of seven studies comprised of 1414 PCOS cases and 1276 controls were included in the current meta-analysis. The pooled analysis showed that overall, there is a significant association between CYP19 rs2414096(G > A) and risk of PCOS (OR = 0.74, 95% CI= 0.62-0.88, p = .0008). In dominant model, GG + AG vs GG and recessive genetic model AA vs AG + GG found a significant association (OR = 1.60,95% CI = 1.10-2.31, p = .01; OR = 0.65,95% CI = 0.45-0.93, p = .02) respectively which indicates that GG phenotype might be risk factor for PCOS development. In stratified subgroup analysis, there was significant association between CYP19 rs2414096 polymorphism and PCOS risk for non-Indian population only while no association was found with Indian population. Conclusion: Present meta-analysis studies indicate that CYP19 rs2414096 is associated with PCOS risk and important in pathogenesis of PCOS for many populations but for Indian population more studies are required as Indian population comprises of various subpopulations genetically isolated since long.

Identifying genes associated with the development of human polycystic ovary syndrome

The pathophysiology of polycystic ovary syndrome (PCOS) is confusing until today as it is a multifactorial endocrine disorder. It is presented with altered gonadotropin levels, bulky multi-follicular ovaries, infertility, and obesity. This complex pathophysiology is linked with insulin resistance and hyperandrogenism. Hyperandrogenemia significantly contributes towards cosmetic anomalies including hirsutism, acne, and alopecia in the PCOS women. The preexisting insulin resistance in women with PCOS is likely to aggravate the increased levels of androgen. The review findings have shown that in the steroidogenic pathway, ovarian steroidogenesis patterns classify mainly towards the hypertrophy of theca cells along with alteration in the expression of key enzymes. The association of polymorphisms in genes encoding the process of an intricate cascade of steroidogenesis is delineated. The emergence of an unanimously accepted genetic marker for susceptible PCOS was affected based on inconsistent findings. The present study has provided a comprehensive summary of the impact of polymorphisms among the common androgen-related genes to govern the genetic predisposition.

Hyperandrogenism in polycystic ovarian syndrome and role of CYP gene variants: a review

Background

Polycystic ovary syndrome (PCOS) is a multifactorial endocrine disorder characterized by anovulation, hyperandrogenism, and polycystic ovarian morphology. The pathophysiology of PCOS is not clear; however, disturbance in hypothalamic-pituitary-ovarian axis and abnormal steroidogenesis along with genetic and environmental factors act as main contributors to this disorder.

Main text

Hyperandrogenism, the hallmark feature of PCOS, is clinically manifested as hirsutism, acne, and alopecia. Excessive androgen production by ovaries as well as from adrenals contributes to hyperandrogenism. Abnormalities in the neuroendocrine system like increased pulse frequency of gonadotropin-releasing hormone, stimulating the pituitary for excessive production of luteinizing hormone than that of follicle-stimulating hormone is seen in PCOS women. Excess LH stimulates ovarian androgen production, whereas a relative deficit in FSH impairs follicular development. The imbalance in LH: FSH causes proliferation of ovarian theca cells leading to increased steroidogenesis, and ultimately leading to hyperandrogenism in PCOS women. Various genetic factors have been shown to be associated with abnormal steroidogenesis. CYP genes involved in steroidogenesis play an important role in androgen production and are considered as key players in hyperandrogenism in PCOS.

Conclusion

Polymorphisms in CYP genes can aggravate the hyperandrogenic phenotype in women with PCOS by either upregulating or downregulating their expression, thus increasing androgens further. However, this hypothesis needs to be validated by further studies.

Therapeutic Effect of Ecklonia cava Extract in Letrozole-Induced Polycystic Ovary Syndrome Rats

Polycystic ovary syndrome (PCOS) is an endocrinal disorder that afflicts mainly women of childbearing age. The symptoms of PCOS are irregular menstrual cycles, weight gain, subfertility and infertility. However, because the etiology is unclear, management and treatment methods for PCOS are not well established. Recently, natural substances have been used for PCOS therapy. Ecklonia cava (E. cava) is a well-known natural substance that attenuates the effects of inflammation, allergies, and cancer. In this study, we investigated the effects of E. cava extract in rats with PCOS. When rats with letrozole-induced PCOS were exposed to the E. cava extract, the regular estrus cycle was restored, similar to that in placebo rats. Hormone levels, including the levels of testosterone, estrogen, luteinizing hormone (LH), follicle stimulating hormone (FSH), and anti-Müllerian hormone (AMH), were restored to their normal states. Histological analysis revealed that the polycystic ovary symptoms were significantly decreased in the E. cava-treated rats and were comparable to those of normal ovaries. At the transcriptional and translational levels, Ar, and Esr2 levels were markedly increased in the E. cava-treated rats with PCOS compared with the rats with letrozole-induced PCOS. These results suggest that the E. cava extract inhibits the symptoms of PCOS by restoring imbalanced hormonal levels and irregular ovarian cycles in letrozole-induced female rats.

Pharmacogenomics in IVF: A New Era in the Concept of Personalized Medicine

Pharmacogenomics is a promising approach in the field of individualized medicine in in vitro fertilization (IVF) treatment that aims to develop optimized pharmacotherapy depending on the genetic background of each infertile woman, thus to ensure maximum effectiveness of the medication used, with minimal side effects. The unique genetic information of each infertile woman, in combination with already known, as well as new predictors of ovarian response and the progress of pharmacoepigenomics, is anticipated to greatly benefit the process of controlled ovarian stimulation. This review analyses current data on IVF pharmacogenomics, a new approach that is gradually moving to the frontline of modern IVF treatment.

Genetic Variants Associated with Hyperandrogenemia in PCOS Pathophysiology

Polycystic ovary syndrome is a multifactorial endocrine disorder whose pathophysiology baffles many researchers till today. This syndrome is typically characterized by anovulatory cycles and infertility, altered gonadotropin levels, obesity, and bulky multifollicular ovaries on ultrasound. Hyperandrogenism and insulin resistance are hallmark features of its complex pathophysiology. Hyperandrogenemia is a salient feature of PCOS and a major contributor to cosmetic anomalies including hirsutism, acne, and male pattern alopecia in affected women. Increased androgen levels may be intrinsic or aggravated by preexisting insulin resistance in women with PCOS. Studies have reported augmented ovarian steroidogenesis patterns attributed mainly to theca cell hypertrophy and altered expression of key enzymes in the steroidogenic pathway. Candidate gene studies have been performed in order to delineate the association of polymorphisms in genes, which encode enzymes in the intricate cascade of steroidogenesis or modulate the levels and action of circulating androgens, with risk of PCOS development and its related traits. However, inconsistent findings have impacted the emergence of a unanimously accepted genetic marker for PCOS susceptibility. In the current review, we have summarized the influence of polymorphisms in important androgen related genes in governing genetic predisposition to PCOS and its related metabolic and reproductive traits.

The relationship between the CYP19 alleles rs727479A/C, rs700518A/G, and rs700519C/T and pregnancy outcome after assisted reproductive technology in patients with polycystic ovary syndrome in a Chinese population: A population-based study

This study investigated the relationship between the CYP19 alleles, rs727479A/C, rs700518A/G, and rs700519C/T, and pregnancy outcome after assisted reproductive technology (ART) in patients with polycystic ovary syndrome (PCOS). Between January 2012 and September 2015, 293 PCOS patients undergoing ART were randomly selected for the study. According to pregnancy outcome after ART, the patients were assigned to pregnancy and non-pregnancy groups. CYP19 rs727479A/C, rs700518A/G and rs700519C/T genotypes were determined using the denaturing high-performance liquid chromatography (DHPLC) method. Haplotype frequencies of the CYP19 alleles rs727479A/C, rs700518A/G and rs700519C/T were estimated using the SHEsis platform. Logistic regression analysis was employed to analyze the factors influencing the pregnancy outcome after ART. The frequency of the AC + CC genotype of rs727479A/C was higher in the pregnancy group than in the non-pregnancy group. The frequency of the CT + TT genotype of rs700519A/G was also higher in the pregnancy group than in the non-pregnancy group. Haplotype analysis indicated that the AAC and AGT haplotypes both exhibited unfavorable influence on the pregnancy outcome after ART. The AAT and CGT haplotypes were favorable to the pregnancy outcome after ART. Logistic regression analysis suggested that the rs727479A/C AA genotype, the rs700519C/T CC genotype and body mass index (BMI) might exert unfavorable influence on the pregnancy outcome after ART for PCOS patients. These findings indicated that the CYP19 alleles rs727479A/C and rs700519C/T might be associated with the pregnancy outcome after ART in patients with PCOS.

Does elevated progesterone on day of oocyte maturation play a role in the racial disparities in IVF outcomes?

The aim of this study was to evaluate if premature progesterone elevation on the last day of assisted reproduction technique stimulation contributes to racial disparities in IVF outcome. A total of 3289 assisted reproduction technique cycles were evaluated in Latino, Asian, African American, and white women. Live birth was more likely in white women (42.6%) compared with Asian (34.8%) and African American women (36.3%), but was similar to Latino women (40.7%). In all racial groups, progesterone was negatively associated with live birth and the negative effect of progesterone persisted when adjusting for confounders. Although the effect of elevated progesterone was similar in all racial groups, the prevalence of elevated progesterone differed. Progesterone > 1.5 ng/ml occurred in only 10.6% of cycles in white women compared with 18.0% in Latino and 20.2% in Asian women. Progesterone > 2 ng/ml occurred in only 2.3% of cycles in white women compared with 6.3% in Latino, 5.9% in Asian and 4.4% in African American women. The increased prevalence of premature elevated progesterone persisted when controlling for IVF stimulation parameters. In conclusion, premature progesterone elevation had a negative effect on live birth in all racial groups studied. The prevalence of elevated progesterone was higher in racial minorities.

The correlation of aromatase activity and obesity in women with or without polycystic ovary syndrome

Background

This study aimed to investigate the effect of polycystic ovary syndrome (PCOS) on the association of aromatase activity assessed by estradiol-to-testosterone ratio (E₂/T) with body mass index (BMI) in women.

Methods

This was a cohort study in five centers for reproductive medicine in China. Data were collected from July 2012 to December 2013. PCOS patients (n = 785) and non PCOS, healthy, age-matched controls (n = 297) were included. Plasma sex hormones including estradiol (E₂), testosterone (T), follicle stimulating hormone (FSH), and luteinizing hormone (LH) were measured by ELISA, together with BMI and E₂/T being calculated, on the third day of the menstrual cycle. Aromatase activity in PCOS patients with different BMI, T and E₂ levels were compared.

Results

E₂/T was significantly lower (P < 0.05) while BMI was significantly increased (P < 0.05) in PCOS than non-PCOS. No significant difference was observed in E₂/T among different BMI subgroups of either PCOS or control. Ovarian aromatase activity was decreased in PCOS patients which was independent of BMI. Hyperestrogen promoted ovarian aromatase activity, while hyperandrogen inhibited such activity, both in a dose-dependent, biphasic manner.

Conclusions

Ovarian aromatase activity was lower in PCOS, which was independent of BMI. New therapeutic strategies can be developed by targeting aromatase activity for treating PCOS women, especially those with obesity.

Pharmacogenetics of ovarian response

Effective controlled ovarian stimulation (COS) is crucial for IVF outcome. Ovarian response to follicle-stimulating hormone, however, varies widely among women undergoing ovarian stimulation. Advance identification of patients who will elicit a poor or high response to standard treatment would be of great clinical benefit for such patients. Application of pharmacogenetics to ovarian response may predict stimulation success but also help in the adjustment and design of doses prior to treatment. Different studies have examined the impact of variations in follicle-stimulating hormone receptor, biochemical pathways involved in estrogen production and action, folliculogenesis and other aspects. Recently, gene-association studies have tried to identify a number of genetic variations affecting interindividual variability in COS.

Association of aromatase (TTTA)n repeat polymorphisms with central precocious puberty in girls

OBJECTIVE

Precocious puberty is characterized by early activation of the pituitary-gonadal axis. Oestrogen is the final key factor to start the onset of puberty. The cytochrome P450 19A1 (CYP19A1) gene encodes an aromatase that is responsible for the conversion of androgens to oestrogen, which is a key step in oestrogen biosynthesis. The aim of this study was to identify CYP19A1 gene mutations or polymorphisms in girls with central precocious puberty (CPP).

METHODS

We evaluated the frequency of allelic variants of the CYP19A1 exons and the tetranucleotide tandem repeat (TTTA)n in intron 4 in 203 idiopathic central precocious puberty (CPP) girls and 101 normal healthy women.

RESULTS

The genotype analysis of the CYP19A1 (TTTA)n polymorphism revealed six different alleles ranging from seven to 13 repeats. Among the six different repeat alleles detected in this study, the (TTTA)₁₃ repeat allele was only detected in the patient group and carriers of the (TTTA)₁₃ allele were significantly associated with an increased risk of CPP (OR = 1·509, 95% CI = 1·425-1·598, P = 0·033). Carriers of the (TTTA)₁₃ repeat allele were significantly younger at pubertal onset and had higher levels of oestrogen than noncarriers of the (TTTA)₁₃ repeat allele. Although nine polymorphisms were detected in exons of the CYP19A1 gene, no clinical significance was observed.

CONCLUSION

In this study, carriers of a higher repeat (TTTA)₁₃ polymorphism in intron 4 of the CYP19A1 gene had higher levels of oestrogen. Those carrying the (TTTA)₁₃ repeat allele may have a higher risk of developing CPP.