A cross-sectional study to assess any possible linkage of C/T polymorphism in CYP17A1 gene with insulin resistance in non-obese women with polycystic ovarian syndrome

CYP17A1 (rs74357) polymorphism and polycystic ovary syndrome risk: a systemic review and meta-analysis

BACKGROUND AND AIM

To investigate the association between CYP17A1 (rs74357) polymorphism and the risk of Polycystic Ovary Syndrome (PCOS).

METHODS

Literature on the association of CYP17rs74357 gene polymorphism and susceptibility to PCOS was retrieved by searching databases such as PubMed, Science Direct, Google Scholar and Embase from. The association measure was analyzed using an Odds Ratio (OR) and 95% Confidence Interval (CI). All the statistical analyses were executed using CMA 3.0 Software.

RESULTS

In the present meta-analysis,24 studies including 3462 PCOS and 2898 controls were analyzed. The overall results validated that the 17 CYP17 T/C (rs74357) gene polymorphism was significantly associated with PCOS risk in 5 genetic models: recessive model (fixed and random effect), dominant model (random effect), CC vs. TT (fixed effect), CT vs. TT (fixed effect), and allele contrast (random effect). Stratified analyses by ethnicity/country also detected significant association between Asian and Caucasian under the recessive, dominant, CC vs. TT, CC vs. CT, and the allele contrast models.

CONCLUSIONS

In the present study, CYP17 T/C (rs74357) gene polymorphism increase the susceptibility of PCOS, and the recessive C allele, can be proposed as a predictive factor for the risk of PCOS or an important pathway in PCOS associated metabolic and hormonal dysregulation especially insulin resistance.However, larger sample size andmultiracial studies are needed in the future to confirm the findings.

The interplay between androgens and the immune response in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a metabolic-reproductive-endocrine disorder that, while having a genetic component, is known to have a complex multifactorial etiology. As PCOS is a diagnosis of exclusion, standardized criteria have been developed for its diagnosis. The general consensus is that hyperandrogenism is the primary feature of PCOS and is associated with an array of physiological dysfunctions; excess androgens, for example, have been correlated with cytokine hypersecretion, adipocyte proliferation, and signaling pathway dysregulation. Another key feature of PCOS is insulin resistance, resulting in aberrant glucose and fatty acid metabolism. Additionally, the immune system plays a key role in PCOS. Hyperandrogenism stimulates some immune cells while it inhibits others, thereby disrupting the normal balance of immune cells and creating a state of chronic inflammation. This low-grade inflammation could contribute to infertility since it induces ovarian dysfunction. This dysregulated immune response in PCOS exhibits autoimmunity characteristics that require further investigation. This review paper examines the relationship between androgens and the immune response and how their malfunction contributes to PCOS.

The Association of CYP17A1, CYP19A1, and SHBG Gene Polymorphisms in Polycystic Ovary Syndrome Susceptibility: A Systematic Review and Meta-Analysis

Objective: To elucidate the relationship between CYP17A1/CYP19A1/SHBG gene polymorphisms and PCOS susceptibility.

Methods: We searched multiple databases from inception to December 2020 and meta analysis was conducted to elucidate the relationship between gene polymorphisms and PCOS risk.

Results: 26 studies were included, comprising 4860 PCOS and 4043 controls. CYP17A1 rs743572 polymorphisms were found to be negatively associated with PCOS risk under dominant model (p = 0.017, OR = 0.83, 95%CI 0.72–0.97, I² = 74.80%, P_{heterogeneity} = 0.000) in the general population while neither CYP19A1 rs2414096 polymorphisms (p = 0.578, OR = 0.87, 95%CI 0.54–1.41, I² = 95.90%, P_{heterogeneity} = 0.000) nor SHBG rs6529 polymorphisms (p = 0.752, OR = 0.99, 95%CI 0.94–1.05, I² = 60.90%, P_{heterogeneity} = 0.012) was associated with PCOS susceptibility under dominant model in the general population.

Conclusion: CYP17A1 rs7435721 polymorphisms might be protective factors against PCOS in general populations.

Systematic Review Registration: https://www.crd.york.ac.uk/prospero/#myprospero, identifier CRD4202122640.

CYP17 T/C (rs74357) gene polymorphism contributes to polycystic ovary syndrome susceptibility: evidence from a meta-analysis

The cytochrome P450 family 17 (CYP17) is associated with hyperandrogenism in women, and the association between CYP17 gene polymorphism and the risk of polycystic ovary syndrome (PCOS) is not definitive. In order to determine whether the CYP17 T/C (rs74357) gene polymorphism is an exposure risk for PCOS, a comprehensive meta-analysis summarizing 19 studies was performed. The pooled odds ratio (OR) and the corresponding 95% CI were measured under five genetic models, and the stratified analyses by ethnicity, Hardy-Weinberg equilibrium, testosterone levels and BMI in controls were carried out to identify the causes of substantial heterogeneity. The overall results validated that the CYP17 T/C (rs74357) gene polymorphism was significantly associated with PCOS risk in four genetic models. Moreover, the outcomes of subgroup analysis by ethnicity indicated that the frequencies of the C allele of CYP17 T/C (rs74357) polymorphism were markedly higher in women from Asia than in Caucasians (T vs C: OR 0.85, 95% CI = 0.74-0.99, P < 0.05). Therefore, these findings suggested that the CYP17 T/C (rs74357) gene polymorphism played an indispensable part in increasing the susceptibility of PCOS when carrying the C allele, which proposed that the polymorphism of the CYP17 gene may be a predictive factor for the risk of PCOS or an important pathway in PCOS-associated metabolic and hormonal dysregulation.

The single-nucleotide polymorphism rs743572 of CYP17A1 shows significant association with polycystic ovary syndrome: a meta-analysis

Polycystic ovary syndrome (PCOS) is a multifactorial reproductive and endocrine disease, believed to be caused by aberrant steroid biosynthesis pathways involving cytochrome P450, 17α-hydroxylase (CYP17A1). This meta-analysis aimed to evaluate the association between CYP17A1 polymorphism rs743572 and PCOS risk. Studies on the CYP17A1 gene were retrieved by searching PubMed, Embase and Web of Science and statistical analyses were performed by STATA software. Fifteen eligible studies were included, dated from January 1994 to 19 November 2020, involving 2277 patients with PCOS and 1913 control individuals. Overall, the results showed that the rs743572 T>C mutation was most likely to be associated with PCOS risk under the recessive model, which was further confirmed by heterogeneity analysis and publication bias detection (CC versus CT + TT, odds ratio [OR] 1.24, 95% confidence interval [CI] 1.02-1.50, P = 0.028, I² = 35.9%). Moreover, subgroup analysis by ethnicity demonstrated that Caucasian but not Asian women carrying the CC genotype of rs743572 had an elevated risk of PCOS (CC versus CT + TT, OR 1.45, 95% CI 1.03-2.06, P = 0.035, I² = 15.10%, six studies). In conclusion, rs743572 is highly likely to be a risk factor for PCOS, and the mutant genotype CC may increase susceptibility to PCOS in Caucasians rather than Asians.

CYP17 gene polymorphic sequence variation is associated with hyperandrogenism in Kashmiri women with polycystic ovarian syndrome

OBJECTIVE

Polycystic ovarian syndrome is a complex reproductive as well as endocrinological disorder characterized by anovulatory dysfunction, androgen excess and polycystic ovarian morphology. Hyperandrogenism is regarded as a cardinal feature of the disease. It is believed that the excess androgens are produced due to abnormality in steroid biosynthesis pathway wherein cytochrome P450, 17α-hydroxylase (CYP17) plays an imperative role. Therefore the objective of the present study was to analyze the T/C polymorphism in 5'UTR of CYP17 gene for its association with PCOS and hyperandrogenism in Kashmiri population.

METHOD

A total of 700 subjects which included 394 PCOS patients and 306 healthy controls were recruited for the study. Their anthropometric, biochemical and hormonal parameters were analyzed. DNA was extracted followed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to analyze the relationship of CYP17 gene polymorphism with PCOS and hyperandrogenism in PCOS.

RESULTS AND CONCLUSION

The allelic as well as genotypic distribution did not show any significant difference between the cases and controls. However, PCOS patients with mutant genotype had significantly higher level of total testosterone and clinical features like FG score, alopecia than those of wild and heterozygous genotype, indicating association with hyperandrogenism in our Kashmiri population.

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.

Pathophysiological mechanisms of gonadotropins- and steroid hormones-related genes in etiology of polycystic ovary syndrome

OBJECTIVES

Polycystic ovary syndrome (PCOS) is an endocrinopathy in women, which, unlike its impact on fertility and health of women, there is no clear understanding about the causal mechanisms of this pathogenesis. The aim of this review paper is to investigate the pathophysiological pathways affecting the PCOS etiology, based on functions of gonadotropins- and steroid hormones-related genes.

MATERIALS AND METHODS

Due to different hormonal and metabolic signs of this complex disorder, different hypotheses are mentioned about etiology of this syndrome. Because of the heterogeneity of the reasons given for this syndrome and the spread of the effective genes in its pathophysiology, most of genes affected by sex-related hormonal imbalances are examined for discriminative diagnosis. 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

In previous studies, it has been well demonstrated that PCOS in some individuals have a genetic origin. Pathophysiological functions of genes are primarily responsible for the synthesis of proteins that have role in PCOS before hyperandrogenism including GnRHR, FSHβ, FSHR, LHCGR, CYP19A1, HSD17B, AR and SHBG, and their effects in PCOS of human have been confirmed.

CONCLUSION

Hormonal imbalances are the first reason mentioned in PCOS etiology, and usually characterized with menstrual irregularities in PCOS women. Hyperandrogenism and gonadotropin secretion disorders are shown in PCOS condition, which are related to steroidogenesis pathways and hypothalamic-pituitary-ovarian axis disturbances, respectively.

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 significance of polymorphism and expression of oestrogen metabolism-related genes in Chinese women with premature ovarian insufficiency

The aim of this study was to investigate whether polymorphism and expression of CYP17, CYP1A1, COMT and SULT1A1 affected the risk of idiopathic primary ovarian insufficiency (POI) in Chinese women. DNA sequencing and real-time PCR were used to detect these genes in 132 cases of idiopathic POI and 132 normal women. A significant increase in the C allele of CYP17 (rs743572) polymorphism was observed in women with POI compared with controls (P_FDR = 0.046). A significant decrease was observed in the C allele of CYP1A1 (rs4646903) in women with POI compared with controls (P_FDR = 0.004). The A allele of COMT (rs4680) polymorphism was more frequent in women with POI compared with controls (P_FDR = 0.029). The genotypic frequency of SULT1A1 (rs9282861) was not significantly different between the two groups. For the relative expression of CYP17 and COMT were statistically significant (both P_FDR = 0.066), with false discovery rate controlled at 0.1. No significant difference was observed in the RNA levels of CYP1A1 and SULT1A1 between the two groups. The frequency of expression of the CYP17 T/C variant tended to be higher and the A allele of COMT polymorphism together with down-regulation of its mRNA expression may be more frequent in Chinese women with idiopathic POI.