Role of Lipotoxicity and Contribution of the Renin-Angiotensin System in the Development of Polycystic Ovary Syndrome

Predicting ART outcomes: The role of ovarian RAS and VEGF in follicular fluid of dominant follicles

As tissue and intracellular RAS have been reported in different organs and systems. there is local RAS in the ovary, called the ovarian renin-angiotensin system (OVRAS). In this study, we investigated the correlation between RAS (total renin, AngII, Ang1-7), vascular endothelial growth factor (VEGF) and E2 in dominant follicular fluid and ovarian reserve capacity and patient age. Moreover, we analyzed its predictive value for assisted reproductive technology (ART) related outcomes. We observed that the concentrations of VEGF in the follicular fluid of dominant follicles in the ≥ 38 year old group were markedly higher than those in the < 30 year old group (P < 0.05). Total renin and AngII levels were positively correlated with normal fertilization rate (P < 0.05). Ang1-7 levels were positively correlated with the number of mature oocytes, oocyte maturation rate and number of 2PN fertilized cells (P < 0.05). Expressions of VEGF were negatively correlated with number of 2PN fertilized cells, number of D3 embryos for blastocyst culture, number of blastocysts formed, number of available embryos and number of high-quality embryos (P < 0.05). Thus, the expressions of OVRAS (total renin, AngII, Ang1-7 and VEGF) in dominant follicular fluid are correlated with ART outcomes.

Cardiovascular Risk Biomarkers in Women with and Without Polycystic Ovary Syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder with an increased risk for cardiovascular disease (CVD) that is enhanced by obesity. This study sought to determine whether a panel of cardiovascular risk proteins (CVRPs) would be dysregulated in overweight/obese PCOS patients, highlighting potential biomarkers for CVD in PCOS.

METHODS

In this exploratory cross-sectional study, plasma levels of 54 CVRPs were analyzed in women with PCOS (n = 147) and controls (n = 97). CVRPs were measured using the SOMAscan proteomic platform (version 3.1), with significant proteins identified through linear models, regression analysis, and receiver operating characteristic (ROC) analysis. Analysis on BMI-matched subsets of the cohort were undertaken. Functional enrichment and protein-protein interaction analyses elucidated the pathways involved.

RESULTS

Eleven CVRPs were dysregulated in PCOS (whole set, without matching for body mass index (BMI) or insulin resistance (IR)): leptin, Interleukin-1 receptor antagonist protein (IL-1Ra), polymeric immunoglobulin receptor (PIGR), interleukin-18 receptor (IL-18Ra), C-C motif chemokine 3 (MIP-1a), and angiopoietin-1 (ANGPT1) were upregulated whilst advanced glycosylation end product-specific receptor, soluble (sRAGE), bone morphogenetic protein 6 (BMP6); growth/differentiation factor 2 (GDF2), superoxide dismutase [Mn] mitochondrial (MnSOD), and SLAM family member 5 (SLAF5) were downregulated versus the controls. In BMI-matched (overweight/obese, BMI ≥ 26 kg/m2) subset analysis, six CVRPs were common to the whole set: ANGPT1 and IL-1Ra were upregulated; and sRAGE, BMP6, GDF2, and Mn-SOD were downregulated. In addition, lymphotactin (XCL1) was upregulated and placenta growth factor (PIGF), alpha-L-iduronidase (IDUA), angiopoietin-1 receptor, and soluble (sTie-2) and macrophage metalloelastase (MMP12) were downregulated. A subset analysis of BMI-matched plus insulin resistance (IR)-matched women revealed only upregulation of tissue factor (TF) and renin in PCOS, potentially serving as biomarkers for cardiovascular risk in overweight/obese women with PCOS.

CONCLUSIONS

A combination of upregulated obesity-related CVRPs (ANGPT1/IL/1Ra/XCL1) and downregulated cardioprotective proteins (sRAGE/BMP6/Mn-SOD/GDF2) in overweight/obese PCOS women may contribute to the increased risk for CVD. TF and renin upregulation observed in the BMI- and IR-matched limited sample PCOS subgroup indicates their potential risk of CVD.

Angiotensin-converting-enzyme gene insertion-deletion polymorphism and renin angiotensin aldosterone system activity in different phenotypes of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common condition. Its pathophysiology involves an interaction between genetic and environmental factors, resulting in different reproductive and metabolic subtypes. Genetic variation in the angiotensin converting enzyme (ACE) gene has been implicated in the pathophysiology of the syndrome. Our project aims to investigate the relationship between the ACE I/D (insertion/deletion) polymorphism and circulating levels of ACE activity, renin and aldosterone in PCOS.

Patients and methods

PCOS and healthy donors were enrolled over 2 years. The Rotterdam criteria were used to segregate 4 phenotypes. Enrolled controls were matched to PCOS patients for body mass index. Clinical data were recorded and blood samples were taken for analysis of ACE I/D polymorphism and biochemical parameters. Hardy-Weinberg equilibrium evaluation, mean/median comparison and Spearman correlation were performed.

Results

A total of 102 women with PCOS and 107 controls were involved in the study. The most common polymorphism was ID, both in the control and PCOS groups. Renin levels in PCOS patients were positively correlated with luteinizing hormone (LH) and anti-mullerian hormone (AMH) in the ID genotype and with testosterone, free androgen index and insulin in the DD genotype.

Conclusion

The ACE I/D variation may influence the pathophysiology of PCOS subtypes, together with an indirect relationship with renin. Our findings may provide valuable therapeutic insights into the management of PCOS, particularly regarding the potential need for ACE inhibitors or renin inhibitors tailored to ACE gene I/D genotypes or specific subtypes.

Effects of AIDiet intervention to improve diet quality, immuno-metabolic health in normal and overweight PCOS girls: a pilot study

This study was conducted in two groups of girls with PCOS (polycystic ovary syndrome) categorized as slim (group N) and overweight-to-obese (group Ov/Ob). The study's primary outcome was to assess the impact of a 12-week anti-inflammatory diet (AIDiet) intervention, without energy deficit, on daily diet quality improvement, evaluated according to the KIDMED index. The secondary outcome was improving inflammatory, redox, hormonal, and metabolic statuses. In the study, which was completed by 13 girls from the Ov/Ob group and 19 girls from the N group, a significant improvement in the mean KIDMED score was obtained. Moreover, the intervention significantly improves concentration of total antioxidant capacity (TAC), fasting insulin, and the homeostatic model assessment for insulin resistance (HOMA-IR) index, in the Ov/Ob group, while both groups experienced a reduction in the concentration of interleukin (IL)-1 and IL-6, tumour necrosis factor (TNF-α), and androstenedione. The AIDiet intervention effectively improved the quality of the subjects' diets, which was associated with the improvement of hormonal and immuno-metabolic markers. However, these changes in normal-weight patients were observed regardless of body weight reduction. ClinicalTrials.gov Identifier NCT04738409.

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 Angiotensin AT2 Receptor: From a Binding Site to a Novel Therapeutic Target

Discovered more than 30 years ago, the angiotensin AT2 receptor (AT2R) has evolved from a binding site with unknown function to a firmly established major effector within the protective arm of the renin-angiotensin system (RAS) and a target for new drugs in development. The AT2R represents an endogenous protective mechanism that can be manipulated in the majority of preclinical models to alleviate lung, renal, cardiovascular, metabolic, cutaneous, and neural diseases as well as cancer. This article is a comprehensive review summarizing our current knowledge of the AT2R, from its discovery to its position within the RAS and its overall functions. This is followed by an in-depth look at the characteristics of the AT2R, including its structure, intracellular signaling, homo- and heterodimerization, and expression. AT2R-selective ligands, from endogenous peptides to synthetic peptides and nonpeptide molecules that are used as research tools, are discussed. Finally, we summarize the known physiological roles of the AT2R and its abundant protective effects in multiple experimental disease models and expound on AT2R ligands that are undergoing development for clinical use. The present review highlights the controversial aspects and gaps in our knowledge of this receptor and illuminates future perspectives for AT2R research. SIGNIFICANCE STATEMENT: The angiotensin AT2 receptor (AT2R) is now regarded as a fully functional and important component of the renin-angiotensin system, with the potential of exerting protective actions in a variety of diseases. This review provides an in-depth view of the AT2R, which has progressed from being an enigma to becoming a therapeutic target.

Profile of Daughters and Sisters of Women With Polycystic Ovary Syndrome: The Role of Proband's Glucose Tolerance

CONTEXT

First-degree relatives of women with polycystic ovary syndrome (PCOS) present hormonal and metabolic alterations compared to girls unrelated to PCOS. It is unknown whether glucose intolerance in the PCOS proband confers a more severe metabolic predisposition on their first-degree relatives.

OBJECTIVE

To determine whether glucose tolerance status in women with PCOS is associated with worsened glucose metabolism and sex hormone levels in their peripubertal daughters or sisters.

DESIGN

Cross-sectional study.

SETTING

Seven academic centers in North America, South America, and Europe.

PATIENTS

Sixty-four pairs of women with PCOS and their daughters or younger sisters aged between 8 and 14 years were recruited. Twenty-five mothers or older sisters with PCOS were glucose intolerant (GI) and 39 were normal glucose tolerant (NGT).

MAIN OUTCOME MEASURES

Beta-cell function estimated by the insulin secretion-sensitivity index-2 (ISSI-2) during an oral glucose tolerance test and by the disposition index during a frequently sampled IV glucose tolerance test. Free testosterone and 17-hydroxyprogesterone (17-OHP) levels.

RESULTS

Being related to a GI PCOS proband was associated with a lower ISSI-2 (P-value = 0.032) after adjusting for ethnicity, body mass index z-score, and pubertal stage. They also had higher free testosterone (P-value = 0.011) and 17-OHP levels compared to girls with an NGT proband, the latter becoming significant after adjusting for confounders (P-value = 0.040).

CONCLUSIONS

Compared to first-degree female relatives of women with PCOS and NGT, first-degree relatives of women with PCOS and GI display lower beta-cell function and hyperandrogenemia, putting them at higher risk of GI and PCOS development.

Association of Macronutrients Composition, Physical Activity and Serum Androgen Concentration in Young Women with Polycystic Ovary Syndrome

The roles of dietary macronutrients and physical activity (PA) in patients with PCOS have not been sufficiently reported, especially in adolescent girls. To address this knowledge gap, we evaluated the associations between serum concentrations of total testosterone (tT), free testosterone (fT), androstenedione (A), dehydroepiandrosterone-sulfate (DHEA-S), sex hormone-binding globulin (SHBG) and dietary macronutrients intake as well as different types and levels of PA. The study population consisted of 96 girls of Caucasian ancestry, aged 14-18 years: 61 participants with polycystic ovary syndrome (PCOS) and 35 healthy controls. Serum tT, fT, A, DHEA-S, and SHBG were determined in fasting blood. Macronutrient intake and PA levels were assessed by using the three-day food record method and the Beliefs and Eating Habits Questionnaire (KomPAN), respectively. We found several positive correlations between dietary macronutrients such as total fat, saturated fatty acids (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), and hormonal parameters across the entire cohort and in healthy girls. A positive correlation between SHBG and total protein consumption as well as an inverse correlation between SHBG and carbohydrate intake could be determined. No correlation between androgens and macronutrients was found in the PCOS group. In contrast, we observed an inverse correlation between androgen concentrations (except of DHEA-S) and "work/school" and/or "leisure time" PA only in PCOS patients. Moreover, the hormone levels differed according to PA intensity. In conclusion, the impact of diet and PA was strikingly different in adolescents with and without PCOS. These findings indicate that disturbed hormonal homeostasis in PCOS, at least in the youngest patients, likely "overtrump" dietary influences, and otherwise, PA offers a therapeutic potential that requires further evaluation of the long-term effects in randomized studies. (ClinicalTrial.gov Identifier: NCT04738409.).

Exploring AT2R and its polymorphism in different diseases: An approach to develop AT2R as a drug target beyond hypertension

The Angiotensin II type 2 receptor (AT2R) is one of the critical components of the renin-angiotensin system (RAS), which performs diverse functions like inhibiting cell differentiation, cell proliferation, vasodilatation, reduces oxidative stress and inflammation. AT2R is relatively less studied in comparison to other components of RAS despite its uniqueness (sex-linked) and diverse functions. The AT2R is differentially expressed in different tissues, and its gene polymorphisms are associated with several diseases. The molecular mechanism behind the association of AT2R and its gene polymorphisms with the diseases remains to be fully understood, which hinders the development of AT2R as a drug target. Single nucleotide polymorphisms (SNPs) in AT2R are found at different locations (exons, introns, promoter, and UTR regions) and were studied for association with different diseases. There may be different mechanisms behind these associations as some AT2R SNP variants were associated with differential expression, the SNPs (A1675G/A1332G) affect the alternate splicing of AT2R mRNA, A1332G genotype results in shortening of the AT2R mRNA and subsequently defective protein. Few SNPs were found to be associated with the diseases in either females (C4599A) or males (T1334C). Several other SNPs were expected to be associated with other similar/related diseases, but studies have not been done yet. The present review emphasizes on the significance of AT2R and its polymorphisms associated with the diseases to explore the precise role of AT2R in different diseases and the possibility to develop AT2R as a potential drug target.

Association of Angiotensin-Converting Enzyme gene polymorphism in Pakistani women with the atypical steroidogenesis in Polycystic ovarian syndrome: A case-control study

Background

Polymorphism in the angiotensin-converting enzyme gene (ACE) is responsible for elevated ACE concentrations in plasma. High ACE levels induce insulin resistance and hyperandrogenism, which are the main attributes of polycystic ovary syndrome (PCOS). Therefore, it was hypothesized that I/D polymorphism plays a role in the pathogenesis of PCOS.

Objective

A case-control study was designed to investigate the association of I/D polymorphism of the ACE gene with PCOS in Pakistani women of reproductive age.

Methods

ACE I/D polymorphism was assessed in 252 women of age group 16–40 years. For genotypic analysis, PCR amplification of genomic DNA was carried out. Statistical analysis was performed to interpret the results using SPSS software.

Results

Our study showed that PCOS women were more likely to have a high body mass index and waist circumferences. Most PCOS patients had menstrual irregularities 99.3%, hirsutism 75.2% and cysts in ovaries 66.6%, along with other hyperandrogenic conditions (P-value = 0.001). The genotypic and allelic frequencies were significantly different between patients and controls. There was a significant association of three genotypes with the ratio of LH: FSH among PCOS patients (P = 0.05). Anthropometric characters, comorbidities, clinical symptoms, and PCOS conditions showed no statistical significance with ACE polymorphism.

Conclusions

ACE I/D polymorphism was not found associated with clinical conditions of PCOS in women of reproductive age. However, it was associated with atypical steroidogenesis. So, it indicates that ACE I/D polymorphism aggravates the pathogenesis of PCOS.

The Goto-Kakizaki rat is a spontaneous prototypical rodent model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is characterized by an oligo-anovulation, hyperandrogenism and polycystic ovarian morphology combined with major metabolic disturbances. However, despite the high prevalence and the human and economic consequences of this syndrome, its etiology remains unknown. In this study, we show that female Goto-Kakizaki (GK) rats, a type 2 diabetes mellitus model, encapsulate naturally all the reproductive and metabolic hallmarks of lean women with PCOS at puberty and in adulthood. The analysis of their gestation and of their fetuses demonstrates that this PCOS-like phenotype is developmentally programmed. GK rats also develop features of ovarian hyperstimulation syndrome. Lastly, a comparison between GK rats and a cohort of women with PCOS reveals a similar reproductive signature. Thus, this spontaneous rodent model of PCOS represents an original tool for the identification of the mechanisms involved in its pathogenesis and for the development of novel strategies for its treatment.

Effect of fish oil and telmisartan on dehydroepiandrosterone-induced polycystic ovarian syndrome in rats: The role of oxidative stress, transforming growth factor beta-1, and nuclear factor kappa B

Our aim was to explore the effect of telmisartan and/or fish oil on dehydroepiandrosterone (DHEA)-induced PCOS in rats. Sixty female rats were divided into six equal groups as follows: Control; DHEA-induced PCOS; DHEA + Telmisartan; DHEA + Fish oil; DHEA + Carboxymethyl cellulose; and DHEA + Telmisartan +Fish oil group. Plasma sex hormones, anthropometric measurements, and the glycemic indices were measured. Tissue oxidative stress parameters and the proinflammatory cytokines were assessed. The ovaries were subjected to histopathological and electron microscopic examination. Telmisartan and/or fish oil induced significant improvement of insulin resistance with amelioration of oxidative stress and inflammation compared to PCOS group. Also, telmisartan and/or fish oil restored the hormonal levels and the anthropometric measurements to the normal values. This was significant with telmisartan/fish oil combination compared to the use of each of these agents alone. In conclusion, this combination may represent a promising hope for amelioration of PCOS.

GLP-1/GLP-1R Signaling Regulates Ovarian PCOS-Associated Granulosa Cells Proliferation and Antiapoptosis by Modification of Forkhead Box Protein O1 Phosphorylation Sites

As the major cause of female anovulatory infertility, polycystic ovary syndrome (PCOS) affects a great proportion of women at childbearing age. Although glucagon-like peptide 1 receptor agonists (GLP-IRAs) show therapeutic effects for PCOS, its target and underlying mechanism remains elusive. In the present study, we identified that, both in vivo and in vitro, GLP-1 functioned as the regulator of proliferation and antiapoptosis of MGCs of follicle in PCOS mouse ovary. Furthermore, forkhead box protein O1 (FoxO1) plays an important role in the courses. Regarding the importance of granulosa cells (GCs) in oocyte development and function, the results from the current study could provide a more detailed illustration on the already known beneficial effects of GLP-1RAs on PCOS and support the future efforts to develop more efficient GLP-1RAs for PCOS treatment.