Some New Thoughts on the Pathophysiology and Genetics of Polycystic Ovary Syndrome

Potential exacerbation of polycystic ovary syndrome by saccharin sodium Via taste receptors in a letrozole rat model

The most common cause of anovulatory infertility is polycystic ovarian syndrome (PCOS), which is closely associated with obesity and metabolic syndrome. Artificial sweetener, notably saccharin sodium (SS), has been utilized in management of obesity in PCOS. However, accumulating evidence points towards SS deleterious effects on ovarian physiology, potentially through activation of ovarian sweet and bitter taste receptors, culminating in a phenotype reminiscent of PCOS. This research embarked on exploration of SS influence on ovarian functions within a PCOS paradigm. Rats were categorized into six groups: Control, Letrozole-model, two SS groups at 2 dose levels, and two groups receiving 2 doses of SS with Letrozole. The study underscored SS capability to potentiate PCOS-related anomalies. Elevated cystic profile with outer thin granulosa cells, were discernible. This owed to increased apoptotic markers as cleaved CASP-3, mirrored by high BAX and low BCL-2, with enhanced p38-MAPK/ERK1/2 pathway. This manifestation was accompanied by activation of taste receptors and disruption of steroidogenic factors; StAR, CYP11A1, and 17β-HSD. Thus, SS showed an escalation in testosterone, progesterone, estrogen, and LH/FSH ratio, insinuating a perturbation in endocrine regulation. It is found that there is an impact of taste receptor downstream signaling on ovarian steroidogenesis and apoptosis instigating pathophysiological milieu of PCOS.

Assessment of the Effect of Leonurine Hydrochloride in a Mouse Model of PCOS by Gene Expression Profiling

Polycystic ovary syndrome (PCOS) is an endocrine disease commonly associated with metabolic disorders in females. Leonurine hydrochloride (Leo) plays an important role in regulating immunity, tumours, uterine smooth muscle, and ovarian function. However, the effect of Leo on PCOS has not been reported. Here, we used dehydroepiandrosterone to establish a mouse model of PCOS, and some mice were then treated with Leo by gavage. We found that Leo could improve the irregular oestros cycle of PCOS mice, reverse the significantly greater serum testosterone (T) and luteinising hormone (LH) levels, significantly reduce the follicle-stimulating hormone (FSH) level, and significantly increase the LH/FSH ratio of PCOS mice. Leo could also change the phenomenon of ovaries in PCOS mice presented with cystic follicular multiplication and a lacking corpus luteum. Transcriptome analysis identified 177 differentially expressed genes related to follicular development between the model and Leo groups. Notably, the cAMP signalling pathway, neuroactive ligand-receptor interactions, the calcium signalling pathway, the ovarian steroidogenesis pathway, and the Lhcgr, Star, Cyp11a, Hsd17b7, Camk2b, Calml4, and Phkg1 genes may be most related to improvements in hormone levels and the numbers of ovarian cystic follicles and corpora lutea in PCOS mice treated by Leo, which provides a reference for further study of the mechanism of Leo.

Potentials of curcumin against polycystic ovary syndrome: Pharmacological insights and therapeutic promises

Polycystic ovary syndrome (PCOS) is a common hormonal disorder among women (4%-20%) when the ovaries create abnormally high levels of androgens, the male sex hormones that are typically present in women in trace amounts. The primary characteristics of PCOS include oxidative stress, inflammation, hyperglycemia, hyperlipidemia, hyperandrogenism, and insulin resistance. Generally, metformin, spironolactone, eflornithine and oral contraceptives are used to treat PCOS, despite their several side effects. Therefore, finding a potential candidate for treating PCOS is necessary. Curcumin is a major active natural polyphenolic compound derived from turmeric (Curcuma longa). A substantial number of studies have shown that curcumin has anti-inflammatory, anti-oxidative stress, antibacterial, and anti-apoptotic activities. In addition, curcumin reduces hyperglycemia, hyperlipidemia, hyperandrogenism, and insulin resistance in various conditions, including PCOS. The review highlighted the therapeutic aspects of curcumin against the pathophysiology of PCOS. We also offer a hypothesis to improve the development of medicines based on curcumin against PCOS.

Do Androgenic Pattern, Insulin State and Growth Hormone Affect Cardiorespiratory Fitness and Strength in Young Women with PCOS?

In this study, cardiorespiratory fitness (CRF) and strength level were assessed in women with and without polycystic ovary syndrome (PCOS), matched for age, body composition, androgenic pattern and insulinemic pattern. Patients with and without PCOS were evaluated at the Endocrinology Unit and Sport Medicine Division to assess endocrinological (insulinemic, androgenic pattern and growth hormone), anthropometric (with DEXA) and functional parameters (with cardiopulmonary exercise test and handgrip test), as well as physical activity level (with the Global Physical Activity Questionnaire). A total of 31 patients with PCOS and 13 controls were included. No statistically significant differences were found between groups in terms of age, body mass index, body composition, androgenic pattern, insulin state, growth hormone and physical activity level. The PCOS group demonstrated significantly better cardiorespiratory fitness (VO₂max per kg (30.9 ± 7.6 vs. 24.8 ± 4.1 mL/kg/min; p = 0.010), VO₂max per kg of fat-free mass (52.4 ± 8.9 vs. 45.3 ± 6.2 mL/kg/min; p = 0.018)), strength levels (handgrip per kg (0.36 ± 0.09 vs. 0.30 ± 0.08; p = 0.009), handgrip per kg of fat-free mass (13.03 ± 2.32 vs. 11.50 ± 1.91; p = 0.001)) and exercise capacity (METs at test (14.4 ± 2.72 vs. 12.5 ± 1.72 METs; p = 0.019)). In this study, women with PCOS showed a better cardiorespiratory fitness and strength than the control group. The only determinant that could explain the differences observed seems to be the presence of the syndrome itself. These results suggest that PCOS per se does not limit exercise capacity and does not exclude good functional capacity.

Low-dose spironolactone abates cardio-renal disorder by reduction of BAX/inflammasome expression in experimentally induced polycystic ovarian syndrome rat model

The impact of low-dose spironolactone (LSPL), on polycystic ovarian syndrome (PCOS)- associated cardio-renal disorder is unknown. Therefore, the present study hypothesized that LSPL would ameliorate cardio-renal disorders in experimental PCOS animals. Eight-week-old Female Wistar rats were allotted into three groups. The control group received vehicle (distilled water; p.o.), LET-treated group designated as PCOS group received letrozole (1 mg/kg; p.o.), while PCOS+LSPL received letrozole and LSPL (0.25 mg/kg, p.o.). The treatment was done once daily for 21 days uninterrupted. The experimental PCOS rats were characterized with insulin resistance as well as, elevated testosterone and LH/FSH with a significant increase in cardiac and renal lipid profile, oxidative stress, inflammatory biomarkers (NF-κB and TNF-α), LDH and lactate content and decrease in cardiac and renal antioxidant system (GPX and GSH) compared with the control rats. There was also a significant increase in cardiac GGT but not renal GGT activity in PCOS animals. In addition, immunohistochemical assessment of cardiac and renal tissue showed significant expression of inflammasome and BAX in animals with PCOS. Nevertheless, these perturbations were attenuated following the administration of LSPL. Collectively, the present results suggests that LSPL attenuates PCOS-associated cardio-renal disorders by reduction of oxidative stress and BAX/Inflammasome expression.

The expression profile of WNT/β-catanin signalling genes in human oocytes obtained from polycystic ovarian syndrome (PCOS) patients

Polycystic ovarian syndrome (PCOS) is a chronic hormonal turmoil that is demonstrated in 2.2-27% of women of pre-menopausal age. This disease is a complex multigenic disorder that results from the interaction between excess androgen expression, genetic susceptibility and environmental influences. PCOS is associated with 40% of female infertility and endometrial cancer. The WNT/β-catenin signalling transduction pathway regulates aspects of cell proliferation, migration and cell fate determination in the tissue along with early embryonic development and controls the proper activation of the female reproductive system, along with regulating hormonal activity in ovarian granulosa cells. In the current study, we investigated the expression profiles of WNT/β-catenin signalling pathway genes (AXIN2, FZD4, TCF4, WNT3, WNT4, WNT5A, WNT7A, WNT1, APC, GSK3B and β-catenin) in a total of 13 oocyte samples. Seven of these samples were from polycystic women and six were from healthy women. The results of this study displayed the absence of expression of AXIN2, FZD4, TCF4, WNT5A, WNT3, WNT4 and WNT7A genes in ovaries from women with PCOS and from healthy women. While APC and β-catenin expression levels were similar in the oocytes of both patients and controls, conversely, WNT1 and GSK3β genes both showed elevated expression in the oocytes of patients with PCOS, therefore suggesting an association between aberrant expression of WNT1 and GSK3β and the pathogenesis of PCOS. The observations of the current study could be helpful to provide evidence regarding the pathogenesis of PCOS and its treatment.

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.

Polycystic ovary syndrome and infertility: an update

Polycystic ovarian syndrome is the most well-known endocrine condition among women of this generation (PCOS). Symptoms of hyperandrogenism, irregular menstrual periods, and insulin resistance are all traits associated with PCOS. In women with PCOS, the chance of having problems including infertility, insulin resistance, and type 2 diabetes increases. The PCOS board hopes to reduce body weight and insulin levels, restore fertility, control excessive hair growth on the body or scalp, re-establish the regular feminine cycle, and avoid misunderstandings. Insulin sensitizers have been one of the most common metabolic modulators, but their effectiveness has been sporadic. Insulin resistance, followed by thiazolidinediones, is central to the pathophysiology of PCOS, with metformin having nearly similar efficacy. In the management of PCOS, statins and incretins are newer therapies with obvious metabolic targets. Vitamin D, acarbose, and myoinositol are just a few of the reciprocal and optional clinical treatments that have been proved to be useful in the treatment of PCOS. The number of viable methods for dealing with PCOS-related infertility has increased as well. Despite the fact that clomiphene citrate (CC) has long been the gold standard for ovulation induction in the event of ovulatory infertility, aromatase inhibitors can induce ovulation with results that are nearly identical to or better than those reported with CC, aromatase inhibitors can cause ovulation with results that are nearly identical to or better than those reported with CC. Ovarian incitement conventions that intelligently utilize gonadotropins, gonadotropin-delivering hormone rivals, the approach of ovarian boring, and assisted conceptive advancements with in vitro oocyte development indicate an expanding level of therapeutic progress.

High fructose-enriched diet synergistically exacerbates endocrine but not metabolic changes in letrozole-induced polycystic ovarian syndrome in Wistar rats

Background

Polycystic Ovarian Syndrome (PCOS) is a multifactorial endocrine-metabolic disorder that highly contributes to the prevalence of infertility globally. The increased consumption of refined carbohydrate, particularly fructose has been associated with pandemic metabolic disorders, including in women of reproductive age. However, the effects of high fructose consumption (FRD) on endocrine and metabolic disorders associated with PCOS are not clear. Therefore, this study investigated the effects of FRD on endocrine/metabolic changes in letrozole-induced PCOS in Wistar rats.

Materials and methods

Twenty-eight adult female Wistar rats were randomly allotted into 4 groups and treated with vehicle, letrozole (LET; 0.5 mg/kg), FRD (D-fructose chow pellet mixture) and LET + FRD. The treatment lasted for 21days.

Results

Data showed a significant increase in ovarian weight, liver weight, luteinising hormone (LH), testosterone and decrease in follicle stimulating hormone as well as moderate histopathological changes in the fallopian tube, uterus and liver of animals with PCOS. FRD-treated group showed a significant increase in ovarian weight and liver weight but no significant alteration in hormonal profile or histopathological changes in uterus and fallopian tube. However, FRD significantly altered hormonal profile with consequent histopathological changes in fallopian tube and uterus but FRD did not alter ovarian/liver weight or blood glucose in animals with PCOS when compared with animals without PCOS.

Conclusion

The present results demonstrate that FRD synergistically aggravates endocrine but not metabolic changes in PCOS, suggesting that FRD might deteriorate endocrine-related phenotypes in PCOS.

Interleukin 17A deficiency alleviates fluoride-induced testicular injury by inhibiting the immune response and apoptosis

The reproductive toxicity of fluoride (F) has been verified by various epidemiological and experimental studies. Our previous work suggested that the interleukin 17A (IL-17A) is involved in the testicular damage induced by excessive F exposure. In this study, we further investigated the role of IL-17A in F-induced testicular injury. Wild type (WT) and IL-17A knockout (IL-17A^-/-) mice were exposed to 0, 25, 50, or 100 mg/L sodium fluoride (NaF) for 90 days. We found that exposure to excessive F levels caused testicular damage, decreased semen quality, negatively affected testicular morphology, and increased the inflammatory response. Specifically, excessive F intake increased the expression levels of IL-17A in the testis and increased the protein levels of Act1, NF-κB, IL-17R, C/EBP-α, and TRAF6 in the IL-17A signaling pathway. The increase in IL-17A expression corresponded to increases expression of IL-17R, IL-6, IL-23, IL-1β, TGF-β and TNF-α as assessed by RT-PCR and ELISA assays. Remarkably, IL-17A knockout in mice ameliorated the effects of F on testicular damage, semen quality, testicular morphology, and the immune response. Additionally, we found the in vitro exposure of Leydig cells to NaF and recombinant IL-17A led to abnormal apoptosis and a decrease in testosterone secretion. Our findings prove that IL-17A plays a key role in the exacerbation of testicular injuries in F-exposed mice, and that IL-17A deficiency can alleviate F-induced injury by inhibiting the immune response and apoptosis in the testis. These data suggest that targeting IL-17A may be a useful therapeutic strategy for treating F-mediated toxicity in the testis.

Impact of Increased Oxidative Stress on Cardiovascular Diseases in Women With Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a complex disorder that affects around 5% to 10% of women of childbearing age worldwide, making it the most common source of anovulatory infertility. PCOS is defined by increased levels of androgens, abnormal ovulation, irregular menstrual cycles, and polycystic ovarian morphology in one or both ovaries. Women suffering from this condition have also been shown to frequently associate certain cardiovascular comorbidities, including obesity, hypertension, atherosclerosis, and vascular disease. These factors gradually lead to endothelial dysfunction and coronary artery calcification, thus posing an increased risk for adverse cardiac events. Traditional markers such as C-reactive protein (CRP) and homocysteine, along with more novel ones, specifically microRNAs (miRNAs), can accurately signal the risk of cardiovascular disease (CVD) in PCOS women. Furthermore, studies have also reported that increased oxidative stress (OS) coupled with poor antioxidant status significantly add to the increased cardiovascular risk among these patients. OS additionally contributes to the modified ovarian steroidogenesis, consequently leading to hyperandrogenism and infertility. The present review is therefore aimed not only at bringing together the most significant information regarding the role of oxidative stress in promoting CVD among PCOS patients, but also at highlighting the need for determining the efficiency of antioxidant therapy in these patients.

Colocalization of Polycystic Ovary Syndrome Candidate Gene Products in Theca Cells Suggests Novel Signaling Pathways

Genome-wide association studies identified loci associated with polycystic ovary syndrome (PCOS), including those near the LH receptor gene (LHCGR), a clathrin-binding protein (DENND1A) that functions as a guanine nucleotide exchange factor, and the gene encoding RAB5B, a GTPase involved in vesicular trafficking. We proposed that these three PCOS loci could be assembled into a functional network that contributes to altered gene expression in theca cells, resulting in increased androgen synthesis. The functional significance of this network was supported by our discovery that a truncated protein splice variant of the DENND1A gene, termed DENND1A.V2, is elevated in PCOS theca cells, and that forced expression of DENND1A.V2 in normal theca cells increased CYP11A1 and CYP17A1 expression and androgen synthesis, a hallmark of PCOS. In this study, we demonstrate the colocalization of LHCGR, DENND1AV.2, and RAB5B proteins in various cellular compartments in normal and PCOS theca cells by immunofluorescence. Human chorionic gonadotropin and forskolin stimulation was shown to affect the cytoplasmic distribution of LHCGR, DENND1A.V2, and RAB5B. DENND1A.V2 accumulated in the nuclei of the theca cells. Moreover, PCOS theca cells, following forskolin treatment, had a significantly greater relative abundance of nuclear DENND1A.V2. RAB5B also accumulated in the nuclei of PCOS theca cells treated with forskolin. In contrast, LHCGR did not enter the nucleus. This cytological evidence, and the previously reported increase in androgen biosynthesis with forced expression of DENND1A.V2 in normal theca cells, raises the possibility that DENND1A.V2 and RAB5B participate in increasing transcription of genes involved in androgen synthesis.

Naturally Occurring and Experimentally Induced Rhesus Macaque Models for Polycystic Ovary Syndrome: Translational Gateways to Clinical Application

Indian rhesus macaque nonhuman primate models for polycystic ovary syndrome (PCOS) implicate both female hyperandrogenism and developmental molecular origins as core components of PCOS etiopathogenesis. Establishing and exploiting macaque models for translational impact into the clinic, however, has required multi-year, integrated basic-clinical science collaborations. Paradigm shifting insight has accrued from such concerted investment, leading to novel mechanistic understanding of PCOS, including hyperandrogenic fetal and peripubertal origins, epigenetic programming, altered neural function, defective oocytes and embryos, adipogenic constraint enhancing progression to insulin resistance, pancreatic decompensation and type 2 diabetes, together with placental compromise, all contributing to transgenerational transmission of traits likely to manifest in adult PCOS phenotypes. Our recent demonstration of PCOS-related traits in naturally hyperandrogenic (High T) female macaques additionally creates opportunities to employ whole genome sequencing to enable exploration of gene variants within human PCOS candidate genes contributing to PCOS-related traits in macaque models. This review will therefore consider Indian macaque model contributions to various aspects of PCOS-related pathophysiology, as well as the benefits of using macaque models with compellingly close homologies to the human genome, phenotype, development and aging.

miRNA Profiling Reveals miRNA-130b-3p Mediates DENND1A Variant 2 Expression and Androgen Biosynthesis

Polycystic ovary syndrome (PCOS) is a common endocrine disorder of reproductive-age women involving overproduction of ovarian androgens and, in some cases, from the adrenal cortex. Family studies have established that PCOS is a complex heritable disorder with genetic and epigenetic components. Several small, noncoding RNAs (miRNAs) have been shown to be differentially expressed in ovarian cells and follicular fluid and in the circulation of women with PCOS. However, there are no reports of global miRNA expression and target gene analyses in ovarian theca cells isolated from normal cycling women and women with PCOS, which are key to the elucidation of the basis for the hyperandrogenemia characteristic of PCOS. With the use of small RNA deep sequencing (miR-seq), we identified 18 differentially expressed miRNAs in PCOS theca cells; of these, miR-130b-3p was predicted to target one of the PCOS genome-wide association study candidates, differentially expressed in neoplastic vs normal cells domain containing 1A (DENND1A). We previously reported that DENND1A variant 2 (DENND1A.V2), a truncated isoform of DENND1A, is upregulated in PCOS theca cells and mediates augmented androgen biosynthesis in PCOS theca cells. The comparison of miR-130b-3p in normal and PCOS theca cells demonstrated decreased miR-130b-3p expression in PCOS theca cells, which was correlated with increased DENND1A.V2, cytochrome P450 17α-hydroxylase (CYP17A1) mRNA and androgen biosynthesis. miR-130b-3p mimic studies established that increased miR130b-3p is correlated with decreased DENND1A.V2 and CYP17A1 expression. Thus, in addition to genetic factors, post-transcriptional regulatory mechanisms via miR-130b-3p underly androgen excess in PCOS. Ingenuity® Pathway Analysis Core Pathway and Network Analyses suggest a network by which miR-130b-3p, DENND1A, the luteinizing hormone/choriogonadotropin receptor, Ras-related protein 5B, and signaling pathways that they potentially target may mediate hyperandrogenism in PCOS.

Human cytochrome P450 enzymes 5-51 as targets of drugs and natural and environmental compounds: mechanisms, induction, and inhibition - toxic effects and benefits

Cytochrome P450 (P450, CYP) enzymes have long been of interest due to their roles in the metabolism of drugs, pesticides, pro-carcinogens, and other xenobiotic chemicals. They have also been of interest due to their very critical roles in the biosynthesis and metabolism of steroids, vitamins, and certain eicosanoids. This review covers the 22 (of the total of 57) human P450s in Families 5-51 and their substrate selectivity. Furthermore, included is information and references regarding inducibility, inhibition, and (in some cases) stimulation by chemicals. We update and discuss important aspects of each of these 22 P450s and questions that remain open.

Hyperandrogenic origins of polycystic ovary syndrome - implications for pathophysiology and therapy

INTRODUCTION

Polycystic ovary syndrome (PCOS) diagnosis comprises combinations of female hyperandrogenism, menstrual irregularity and polycystic ovaries. While it is a familial and highly prevalent endocrine disorder, progress towards a cure is hindered by absence of a definitive pathogenic mechanism and lack of an animal model of naturally occurring PCOS.

AREAS COVERED

These include an overview of PCOS and its potential etiology, and an examination of insights gained into its pathogenic origins. Animal models derived from experimentally-induced hyperandrogenism during gestation, or from naturally-occurring PCOS-like traits, most reliably demonstrate reproductive, neuroendocrine and metabolic pathogenesis.

EXPERT OPINION

Genetic studies, while identifying at least 17 PCOS risk genes, account for <10% of women with PCOS. A number of PCOS risk genes involve regulation of gonadotropin secretion or action, suggesting a reproductive neuroendocrine basis for PCOS pathogenesis. Consistent with this notion, a number of animal models employing fetal androgen excess demonstrate epigenetic induction of PCOS-like traits, including reproductive neuroendocrine and metabolic dysfunction. Monkey models are most comprehensive, while mouse models provide molecular insight, including identifying the androgen receptor, particularly in neurons, as mediating androgen-induced PCOS-like programming. Naturally-occurring female hyperandrogenism is also demonstrated in monkeys. Animal models are poised to delineate molecular gateways to PCOS pathogenesis.

Effect of "DXB-2030," a Polyherbal Formulation, on Experimental Polycystic Ovary Syndrome Associated with Hyperandrogenism

The objective of the present study was to evaluate “DXB-2030,” a polyherbal combination of Trigonella foenum-graecum, Aloe vera, Sphaeranthus indicus, Nardostachys jatamansi, and Symplocos racemosa extracts in an experimental model of testosterone propionate (TP), induced polycystic ovary syndrome (PCOS) in female rats. Thirty animals were divided into 3 groups of 10 each; group 1 served as normal control; group 2 was administered with TP and served as positive control; along with TP, group 3 was treated with “DXB-2030” at a dose of 100 mg/kg p.o., for 60 days. At the end of the study period, the animals were subjected for the estimation of serum testosterone levels, oral glucose tolerance test (OGTT), weight of the ovaries, estrous cycle, and histopathological evaluation. An in vitro assay on GLUT4 expression was carried out to understand the effect of “DXB-2030” on insulin resistance. Results showed that treatment with “DXB-2030” reversed the TP-induced changes by increasing the GLUT4 expression and decreasing the body weight, testosterone levels, AUC of glucose in OGTT, and the cystic follicles of the ovaries, thus indicating its beneficial effect in PCOS by ameliorating the metabolic dysfunction and reproductive impairment, which are the pathophysiological conditions associated with PCOS. From the results obtained, it can be concluded that “DXB-2030” was effective in the management of experimental PCOS and hence may be recommended in the treatment of PCOS.

Effect of Hawthorn Leaf Flavonoids in Dehydroepiandrosterone-Induced Polycystic Ovary Syndrome in Rats

OBJECTIVE

To evaluate the potential beneficial effects of hawthorn leaf flavonoids (HLF) against polycystic ovary syndrome (PCOS) in a rat model of disease and elucidate the underlying molecular mechanism.

METHODS

The PCOS model was established by subcutaneous injection of dehydroepiandrosterone (DHEA, 60 mg/kg/day) for 21 consecutive days. HLF (200 mg/kg/day) were orally administered simultaneously or after the injection. The body weight was regularly monitored and recorded. The ovaries were weighed and histologically examined via hematoxylin and eosin staining. The number of follicular cysts was counted under a light microscope. The serous hormones were measured using enzyme-linked immunosorbent assay kits. Insulin resistance (IR) was calculated as HOMA-IR = fasting insulin (µU/L) × fasting glucose (mM)/22.5. The estrous cycle was determined by vaginal smear. The relative expression of tumor necrosis factor-α and interleukin-6 was measured by real-time polymerase chain reaction. The superoxide dismutase activity and malondialdehyde content was determined using commercially available kits.

RESULTS

DHEA induced a significant increase of body weight, ovary weight, number of follicular cysts, serous hormones, IR, inflammatory cytokines, and oxidative stress, and it also impaired the estrous cycle. Oral administration of HLF greatly alleviated these complications. Little toxicity of HLF was observed in our rat model.

CONCLUSION

HLF manifest protective effects against PCOS progression in the animal model, which may hold great promise for future clinical applications.

Clinical Case Seminar: Postmenopausal androgen excess-challenges in diagnostic work-up and management of ovarian thecosis

Postmenopausal hyperandrogenism can be tumour- or non-tumour-related, with pathology residing either in the ovary or adrenal gland(s). The tempo of investigation is determined by the clinical severity of hyperandrogenism (presence/absence of actual virilisation) and degree of serum testosterone elevation. When clinical or biochemical hyperandrogenism is severe, rapidly developing, or associated with hypercortisolism, screening for adrenocortical or ovarian carcinoma with cross-sectional imaging should be prioritised over detailed biochemical evaluation. Adrenal hyperandrogenism is readily characterised, both biochemically and radiologically. By contrast, even a combination of high-resolution imaging with laboratory evaluation, including dynamic endocrine testing, often cannot distinguish between ovarian hyperthecosis (OH) and virilising ovarian tumour (VOT); a definitive diagnosis usually emerging only after histological examination of excised ovaries. VOTs are typically below the resolution-limit of current imaging modalities and exhibit suppression of gonadotropin-dependent androgen secretion with GnRH-analogue therapy. Thus, for well-characterised ovarian hyperandrogenism, laparoscopic bilateral salpingo-oophorectomy may serve both as a diagnostic and therapeutic procedure. Nevertheless, women unable or unwilling to undergo ovarian surgery can be reassured that malignant VOTs are exceedingly rare and that long-term medical therapy with oral antiandrogens or GnRH-analogues is safe and well-tolerated. OH is strongly associated with insulin-resistance, with hyperinsulinaemia acting synergistically with raised gonadotropin levels to stimulate thecal cell hyperplasia and androgen secretion by the postmenopausal ovary, which lacks granulosa cell aromatase activity and thus cannot convert testosterone to 17 beta estradiol. Thus, features of metabolic syndrome may indicate OH, and significant reductions in androgens can thereby potentially be achieved with lifestyle measures and/or insulin-sensitising drugs.

Role of cytochrome b5 in the modulation of the enzymatic activities of cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1)

Cytochrome b5 (cyt b5) is a small hemoprotein that plays a significant role in the modulation of activities of an important steroidogenic enzyme, cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1, CYP17A1). Located in the zona fasciculata and zona reticularis of the adrenal cortex and in the gonads, P450 17A1 catalyzes two different reactions in the steroidogenic pathway; the 17α-hydroxylation and 17,20-lyase, in the endoplasmic reticulum of these respective tissues. The activities of P450 17A1 are regulated by cyt b5 that enhances the 17,20-lyase reaction by promoting the coupling of P450 17A1 and cytochrome P450 reductase (CPR), allosterically. Cyt b5 can also act as an electron donor to enhance the 16-ene-synthase activity of human P450 17A1. In this review, we discuss the many roles of cyt b5 and focus on the modulation of CYP17A1 activities by cyt b5 and the mechanisms involved.

Intracytoplasmic oxidative stress reverses epigenetic modifications in polycystic ovary syndrome

In polycystic ovary syndrome (PCOS), substantial genetic and environmental alterations, along with hyperandrogenism, affect the quality of oocytes and decrease ovulation rates. To determine the mechanisms underlying these alterations caused specifically by an increase in plasma androgens, the present study was performed in experimentally-induced PCOS mice. As the study model, female B6D2F1 mice were treated with dehydroepiandrosterone (DHEA, 6 mg per 100 g bodyweight). After 20 days, oocytes at the germinal vesicle and metaphase II stages were retrieved from isolated ovaries and subsequent analyses of oocyte quality were performed for each mouse. DHEA treatment resulted in excessive abnormal morphology and decreased polar body extrusion rates in oocytes, and was associated with an increase in oxidative stress. Analysis of fluorescence intensity revealed a significant reduction of DNA methylation and dimethylation of histone H3 at lysine 9 (H3K9) in DHEA-treated oocytes, which was associated with increased acetylation of H4K12. Similarly, mRNA expression of DNA methyltransferase-1 and histone deacetylase-1 was significantly decreased in DHEA-treated mice. There was a significant correlation between excessive reactive oxygen species (ROS) production and increased histone acetylation, which is a novel finding and may provide new insights into the mechanism causing PCOS. The results of the present study indicate that epigenetic modifications of oocytes possibly affect the quality of maturation and ovulation rates in PCOS, and that the likely mechanism may be augmentation of intracytoplasmic ROS.

Endocrine and Metabolic Profile of Different Phenotypes of Polycystic Ovarian Syndrome

BACKGROUND

Polycystic ovarian syndrome (PCOS) is a common endocrinopathy associated with wide heterogeneity and serious clinical implications. Prevalence and characteristics of different phenotypes are not well defined. Therefore, this study was planned to determine the prevalence of four phenotypes of PCOS and to evaluate their endocrine and metabolic parameters including insulin resistance and metabolic syndrome with respect to controls.

METHODS

This observational, case-control study was conducted in the gynecology outpatient department of a tertiary care center where 161 PCOS and 50 non-PCOS women were recruited and investigated.

RESULTS

All phenotypes of PCOS had higher BMI with respect to controls (P < 0.000). Overweight women were maximum in phenotype H + O followed by phenotype H + P. Significantly higher levels of luteinizing hormone (P < 0.01), testosterone (P < 0.0001), were observed in all phenotypes of PCOS as compared to controls. Serum cholesterol (P < 0.026) and triglycerides (P < 0.05) were significantly higher in all PCOS phenotypes compared to controls. Levels of fasting (P < 0.000) and post-prandial (P < 0.009) insulin were significantly higher in all phenotypes of PCOS with respect to controls. Mean insulin resistance (IR) was 24.09 % in PCOS and 2 % in controls, prevalence being highest in H + O phenotype followed by H + O + P. Prevalence of metabolic syndrome in women with PCOS was 36.02 %, being highest in H + O + P followed by H + O and that of control was 10 %.

CONCLUSION

All phenotypes of PCOS had deranged endocrine and metabolic profile compared to controls, but prevalence of IR and metabolic syndrome was maximum in hyperandrogenic phenotypes which require a strict surveillance for prospective metabolic disorders as compared to O + P phenotype.

Effect of oral administration of low-dose follicle stimulating hormone on hyperandrogenized mice as a model of polycystic ovary syndrome

Background

Polycystic Ovary Syndrome (PCOS) is a widespread reproductive disorder characterized by a disruption of follicular growth and anovulatory infertility. In women with PCOS, follicular growth and ovulation can be induced by subcutaneous injections of low doses of follicle stimulating hormone (FSH). The aim of this study was to determine the effect of oral administration of recombinant human FSH (rhFSH) on follicle development in a PCOS murine model. Moreover, since it is unlikely that intact rhFSH is present into the circulation after oral administration, the biological activity of a peptide fragment, derived from the predicted enzymatic cleavage sites with the FSH molecule, was investigated in vitro on cumulus-enclosed oocytes (COCs).

Methods

Female peripubertal mice were injected with dehydroepiandrosterone (DHEA) diluted in sesame oil for 20 consecutive days and orally treated with a saline solution of rhFSH. A control group received only sesame oil and saline solution. At the end of treatments, blood was analyzed for hormone concentrations and ovaries were processed for morphological analysis. The presumptive bioactive peptide was added during in vitro maturation of bovine COCs and the effects on cumulus expansion and on maturation rate were evaluated.

Results

DHEA treatment increased serum levels of testosterone, estradiol and progesterone as well as the percentage of cystic follicles. Orally administered rhFSH restored estradiol level and reduced the percentage of cystic follicles. Despite these results indicating a reduction of the severity of PCOS in the mouse model, the presumptive bioactive peptide did not mimic the effect of rhFSH and failed to induce bovine cumulus expansion and oocyte maturation in vitro.

Conclusions

Although further studies are needed, the present data supports the concept that orally administrated FSH could attenuate some of the characteristic of PCOS in the mouse model.

Electronic supplementary material

The online version of this article (doi:10.1186/s13048-015-0192-9) contains supplementary material, which is available to authorized users.

Structures of human steroidogenic cytochrome P450 17A1 with substrates

The human cytochrome P450 17A1 (CYP17A1) enzyme operates at a key juncture of human steroidogenesis, controlling the levels of mineralocorticoids influencing blood pressure, glucocorticoids involved in immune and stress responses, and androgens and estrogens involved in development and homeostasis of reproductive tissues. Understanding CYP17A1 multifunctional biochemistry is thus integral to treating prostate and breast cancer, subfertility, blood pressure, and other diseases. CYP17A1 structures with all four physiologically relevant steroid substrates suggest answers to four fundamental aspects of CYP17A1 function. First, all substrates bind in a similar overall orientation, rising ∼60° with respect to the heme. Second, both hydroxylase substrates pregnenolone and progesterone hydrogen bond to Asn(202) in orientations consistent with production of 17α-hydroxy major metabolites, but functional and structural evidence for an A105L mutation suggests that a minor conformation may yield the minor 16α-hydroxyprogesterone metabolite. Third, substrate specificity of the subsequent 17,20-lyase reaction may be explained by variation in substrate height above the heme. Although 17α-hydroxyprogesterone is only observed farther from the catalytic iron, 17α-hydroxypregnenolone is also observed closer to the heme. In conjunction with spectroscopic evidence, this suggests that only 17α-hydroxypregnenolone approaches and interacts with the proximal oxygen of the catalytic iron-peroxy intermediate, yielding efficient production of dehydroepiandrosterone as the key intermediate in human testosterone and estrogen synthesis. Fourth, differential positioning of 17α-hydroxypregnenolone offers a mechanism whereby allosteric binding of cytochrome b5 might selectively enhance the lyase reaction. In aggregate, these structures provide a structural basis for understanding multiple key reactions at the heart of human steroidogenesis.

A subpathway-based method of drug reposition for polycystic ovary syndrome

The need for development of new therapeutic agents for polycystic ovary syndrome (PCOS) is urgent due to general lack of efficient and specialized drugs currently available. We aimed to explore the metabolic mechanism of PCOS and inferred drug reposition for PCOS by a subpathway-based method. Using the GSE34526 microarray data from the Gene Expression Omnibus database, we first identified the differentially expressed genes (DEGs) between PCOS and normal samples. Then, we identified 13 significantly enriched metabolic subpathways that may be involved in the development of PCOS. Finally, by an integrated analysis of PCOS-involved subpathways and drug-affected subpathways, we identified 54 novel small molecular drugs capable to target the PCOS-involved subpathways. We also mapped the DEGs of PCOS and a potential novel drug (alprostadil) into purine metabolism pathway to illustrate the potentially active mechanism of alprostadil on PCOS. Candidate agents identified by our approach may provide insights into a novel therapy approach for PCOS.

Overexpression of a DENND1A isoform produces a polycystic ovary syndrome theca phenotype

Polycystic ovary syndrome (PCOS), characterized by increased ovarian androgen biosynthesis, anovulation, and infertility, affects 5-7% of reproductive-age women. Genome-wide association studies identified PCOS candidate loci that were replicated in subsequent reports, including DENND1A, which encodes a protein associated with clathrin-coated pits where cell-surface receptors reside. However, these studies provided no information about functional roles for DENND1A in the pathogenesis of PCOS. DENND1A protein was located in the cytoplasm as well as nuclei of theca cells, suggesting a possible role in gene regulation. DENND1A immunostaining was more intense in the theca of PCOS ovaries. Using theca cells isolated and propagated from normal cycling and PCOS women, we found that DENND1A variant 2 (DENND1A.V2) protein and mRNA levels are increased in PCOS theca cells. Exosomal DENND1A.V2 RNA was significantly elevated in urine from PCOS women compared with normal cycling women. Forced overexpression of DENND1A.V2 in normal theca cells resulted in a PCOS phenotype of augmented CYP17A1 and CYP11A1 gene transcription, mRNA abundance, and androgen biosynthesis. Knock-down of DENND1A.V2 in PCOS theca cells reduced androgen biosynthesis and CYP17A1 and CYP11A1 gene transcription. An IgG specific to DENND1A.V2 also reduced androgen biosynthesis and CYP17 and CYP11A1 mRNA when added to the medium of cultured PCOS theca cells. We conclude that the PCOS candidate gene, DENND1A, plays a key role in the hyperandrogenemia associated with PCOS. These observations have both diagnostic and therapeutic implications for this common disorder.

[Role of genetic and environmental factors in the development of polycystic ovary syndrome]

Polycystic ovary syndrome is the most common heterogeneous endocrine abnormality in women in the reproductive age. The syndrome remains an enigmatic disorder because the aetiology is still unclear. Familial aggreagation is relatively common among patients with polycystic ovary syndrome suggesting a significant genetic component, although the way of inheritance has not been established firmly. The authors review the relevant medical literature and suggest that genetic and environmental factors play a role in the development of polycystic ovary syndrome. To date, no gene has been identified that causes or contributes substantially to the development of a polycystic ovary syndrome phenotype. Polycystic ovarian syndrome is considered to be an oligogenic disorder in which the interaction of a number of genetic and environmental factors determines the heterogeneous clinical and biochemical phenotype. To summarize current evidence the authors conclude, that when we are able to identify and then modify environmental determinants, then we will be able to safeguard better the health of those patients who are predisposed to disease development due to genotype or previous environmental effects.

The 312N variant of the luteinizing hormone/choriogonadotropin receptor gene (LHCGR) confers up to 2·7-fold increased risk of polycystic ovary syndrome in a Sardinian population

OBJECTIVE

Polycystic ovary syndrome (PCOS) is a frequent condition, affecting about 15% of women of reproductive age. Because of its familial occurrence, a multifactorial model of susceptibility, including both genetic and environmental factors, has been proposed. However, the identification of genetic factors has been elusive.

DESIGN

Case-control study aimed at evaluating possible associations between functionally relevant variants of the luteinizing hormone/choriogonadotrophin receptor gene (LHCGR) and PCOS phenotype.

PATIENTS

A total of 198 PCOS and 187 non-PCOS women, aged 14-35 years, of Sardinian origin, were referred to the outpatient clinic of the Department of Obstetrics and Gynaecology of the University of Cagliari (Sardinia). PCOS diagnosis was based on the Rotterdam criteria.

MEASUREMENTS

We determined the genotype of ins18LQ, S291N and S312N variants at the LHCGR locus. Genotype was related to the presence or absence of PCOS and to several clinical and biochemical characteristics.

RESULTS

The presence of at least one 312N allele was strongly associated with PCOS risk (OR, 2·04; 95% CI, 1·32-3·14; χ(2) , 10·47; P = 0·001). 312N homozygosity was associated with a further risk increase (OR, 2·73; 95% CI, 1·25-5·95; χ(2) , 6·65; P = 0·01). The number of ins18LQ alleles was associated with LH serum levels in controls (χ(2) , 8·04, P = 0·017).

CONCLUSIONS

For the first time, we have identified a genetic variant that is strongly associated with PCOS in an isolated population. These results, if confirmed in other cohorts, may provide the opportunity to test the S312N genotype at the LHCGR locus in fertile women to assess the risk of PCOS. The avoidance of triggering factors like weight increase may improve the reproductive outcome of potentially at-risk subjects.

Polycystic ovary syndrome: Implications of measurement of plasma aldosterone, renin activity and progesterone

A positive correlation between aldosterone, inflammatory parameters, blood pressure and metabolic abnormalities in polycystic ovary syndrome (PCOS) has been reported in the early estrogenic phase. The aim of the study was to measure plasma aldosterone, plasma renin activity (PRA) and progesterone on the 21st day of the cycle, in women with PCOS and to consider the interrelationships between these hormones. Sixty-six consecutive normal BMI women with PCOS (median age 24 years, range 21-28 years) and 53 age- and body mass index-matched healthy controls were enrolled in the study. Aldosterone, aldosterone/PRA ratio (ARR) and Homeostasis Model Assessment (HOMA) index were significantly higher (p<0.0001) in PCOS women than controls. Positive correlations were found in PCOS but not in controls between (i) progesterone and aldosterone, (ii) aldosterone and PRA, (iii) PRA and progesterone. Mean blood pressures were within the normal range but significantly higher in PCOS than controls. The increase of plasma aldosterone, ARR and blood pressure in PCOS compared with controls is consistent with an increased mineralocorticoid effector mechanism in PCOS; prolonged therapy with spironolactone could counteract both the hyperandrogenism and reduce future cardiovascular risk.

Loss of PKBβ/Akt2 predisposes mice to ovarian cyst formation and increases the severity of polycystic ovary formation in vivo

Ovarian cysts affect women of all ages and decrease fertility. In particular, polycystic ovarian syndrome (PCOS), in which multiple follicular cysts develop, affects 5–10% of women of reproductive age and can result in infertility. Current non-invasive treatments for PCOS can resolve cysts and restore fertility, but unresponsive patients must undergo severe ovarian wedge resection and resort to in vitro fertilization. PCOS is related to the deregulation of leutinizing hormone (LH) signaling at various levels of the hypothalamic-pituitary-ovarian axis and resultant hyperproduction of androgens. Because insulin resistance and compensatory hyperinsulinemia are observed in 50–70% of individuals with PCOS, deregulated insulin signaling in the ovary is considered an important factor in the disease. Here we report that aged mice specifically lacking the PKBβ (also known as Akt2) isoform that is crucial for insulin signaling develop increased testosterone levels and ovarian cysts, both of which are also observed in insulin-resistant PCOS patients. Young PKBβ knockout mice were used to model PCOS by treatment with LH and exhibited a cyst area that was threefold greater than in controls, but without hyperinsulinemia. Thus, loss of PKBβ might predispose mice to ovarian cysts independently of hyperactive insulin signaling. Targeted therapeutic augmentation of specific PKBβ signaling could therefore provide a new avenue for the treatment and management of ovarian cysts.

Serum insulin patterns and the relationship between insulin sensitivity and glycaemic profile in women with polycystic ovary syndrome

OBJECTIVE

To evaluate serum insulin levels and insulin sensitivity in women with polycystic ovary syndrome (PCOS) in relation to their glycaemic status.

DESIGN

An observational study.

SETTING

A tertiary-level reproductive health centre in Sri Lanka.

SAMPLE

Infertile women diagnosed as having PCOS (n=168) on the basis of the Rotterdam criteria were included in the study.

METHODS

Glycaemic status and serum insulin values were assessed at fasting and at 2 hours after a 75-g oral glucose load and stratified as diabetes mellitus (DM) (10.12%), impaired glucose tolerance (IGT) (23.21%) and normoglycaemia (66.67%). The normoglycaemic group was restratified as groups A (10.7%), B (79.5%) and C (9.8%) on the basis of serum insulin levels, with group A having the lowest and group C the highest values. The Quantitative Insulin Sensitivity Check Index (QUICKI) scores of women with DM and IGT and those in groups A, B and C in the normoglycaemic category were compared.

MAIN OUTCOME MEASURES

Insulin sensitivity in these groups of women.

RESULTS

Body mass index (BMI) exceeded 23 kg/m(2) in 77.38% of the women. In normoglycaemic women with PCOS, insulin sensitivity was highest in group A. In groups B and C, insulin sensitivities corresponded to those found for women with IGT and DM respectively. This pattern was also reflected in the BMI.

CONCLUSIONS

Normoglycaemic women with PCOS are heterogeneous regarding insulin sensitivity. The treatment offered to those with DM and IGT could be extended to subgroups B and C of normoglycaemic subjects. Normoglycaemic women with PCOS with high insulin sensitivity (group A) would not qualify for this treatment.

Genomic biomarkers, androgen pathway and prostate cancer

Prostate cancer is the most frequent male malignancy diagnosed in western countries and the second leading cause of cancer-related deaths. The growth and function of the prostate gland depends on androgens. Owing to the importance of androgens in prostate development, genes involved in androgen biosynthesis and metabolism have been extensively studied. In this review, we address recent progress toward the use of inherited and acquired genetic variants to predict susceptibility and clinical outcomes of prostate cancer patients. Many of these genetic variants involve several genes related to the biosynthesis and metabolism of androgens, such as steroid-5-α-reductase, α polypeptide 2 (SRD5A2), cytochrome P450 (CYP)19A1, CYP17A1, hydroxy-δ-5-steroid dehydrogenase, 3 β- and steroid δ-isomerase 2 (HSD3B2) and androgen receptor (AR). With increasing knowledge, it may be possible to distinguish indolent from aggressive prostate tumors by molecular fingerprinting. Furthermore, with the emergence of new investigative tools, such as microarray platforms and comparative genomic hybridization (CGH) array, a variety of new genomic biomarkers will be available in the future to provide accurate prognostic and monitoring solutions for individualized patient care.

The (TAAAA)n microsatellite polymorphism in the SHBG gene influences serum SHBG levels in women with polycystic ovary syndrome

BACKGROUND

Hyperandrogenaemia is a common feature of polycystic ovary syndrome (PCOS). The sex hormone-binding globulin (SHBG) gene was proposed as being a PCOS candidate gene. A possible influence of the microsatellite polymorphism (TAAAA)(n) in the SHBG gene on serum SHBG levels in PCOS patients was investigated.

METHODS

One hundred and twenty-three PCOS patients and 110 age-matched controls were included in the study. Peripheral blood samples were obtained. Genotyping of the (TAAAA)(n) polymorphism in the SHBG gene was performed. Serum LH, FSH, SHBG and total testosterone concentrations were determined.

RESULTS

SHBG alleles with 6-11 TAAAA repeats were found. None of the SHBG alleles or genotypes were present at a significantly more frequent rate in PCOS patients compared with controls. Serum SHBG levels were significantly lower (P < 0.001) in PCOS patients compared with controls and were found to be strongly influenced by the (TAAAA)(n) SHBG polymorphism, in both the PCOS (55.3%) and control (33.1%) groups of patients.

CONCLUSIONS

The (TAAAA)(n) SHBG gene polymorphism might be an important predictor for serum SHBG levels and, consequently, for hyperandrogenaemic clinical presentation of PCOS.

Ovarian surgery and follicular reserve

In patients with cystic ovarian pathology, such as endometriomas, polycystic ovary syndrome, teratomas or benign tumors, there is a tendency towards abnormal ovarian function. Anovulation and sterility may occur. This review will summarize the normal physiology of the female gonad and the development of oogenesis from initial reproductive age to the menopause. Furthermore, the interaction between ovarian pathology and endocrinology will be described. The main focus is on the technique of ovarian-preserving surgery by laparoscopy. In addition, alternative therapeutic approaches and screening tests will be discussed.

Molecular mechanisms of insulin resistance and associated diseases

Insulin resistance is a state in which higher than normal concentrations of insulin are required for normal response. The most common underlying cause is central obesity, although primary insulin resistance in normal-weight individuals is also possible. Excess abdominal adipose tissue has been shown to release increased amounts of free fatty acids which directly affect insulin signalling, diminish glucose uptake in muscle, drive exaggerated triglyceride synthesis and induce gluconeogenesis in the liver. Other factors presumed to play the role in insulin resistance are tumour necrosis factor alpha, adiponectin, leptin, IL-6 and some other adipokines. Hyperinsulinaemia which accompanies insulin resistance may be implicated in the development of many pathological states, such as hypertension and hyperandrogenaemia. Insulin resistance underlies metabolic syndrome and is further associated with polycystic ovary syndrome and lipodystrophies. When beta-cells fail to secrete the excess insulin needed, diabetes mellitus type 2 emerges, which is, besides coronary heart disease, the main complication of insulin resistance and associated diseases.

Cross-sectional association between markers of inflammation and serum sex steroid levels in the postmenopausal estrogen/progestin interventions trial

BACKGROUND

Standard risk factors do not adequately capture cardiovascular risk in postmenopausal women. We sought to determine the associations between levels of sex steroids and levels of inflammatory markers in postmenopausal women.

METHODS

We analyzed baseline data from a subset of postmenopausal women aged 45-64 years who had stored samples during a randomized controlled trial. We measured levels of C-reactive protein (CRP), interleukin-6 (IL-6), matrix metalloproteinase-9 (MMP-9), soluble intercellular adhesion molecule (sICAM), and circulating sex steroids. Multiple linear regression models were created with each of the following hormone levels as the primary exposure variable: estrone, total estradiol, bioavailable estradiol, total testosterone, bioavailable testosterone, progesterone, and sex hormone-binding globulin (SHBG). Sociodemographic and lifestyle covariates were derived from standardized self-report questionnaires and direct measurement (weight, height).

RESULTS

Mean age of the 623 women was 56 years. After adjustment for age, body mass index (BMI), physical activity, alcohol consumption, and smoking, the bioavailable testosterone level (p = 0.03) was positively and the SHBG level (p < 0.001) was negatively associated with the logCRP level. The increment in CRP level between the highest and lowest quartile of bioavailable testosterone was 1.28 microg/mL. The increment in CRP level between the lowest and highest quartile of SHBG was 2.62 microg/mL. Compared with SHBG or bioavailable testosterone as predictors of logCRP in separate regression models, when both SHBG and bioavailable testosterone were included in the same multivariate linear regression model, only SHBG remained a statistically significant predictor of logCRP. Progesterone level was positively associated with the logMMP-9 level (p < 0.001); no other sex steroid level was associated with the logMMP-9 level. In multiply adjusted models, no association was found between levels of any sex steroid and IL-6 or sICAM level.

FEM1A is a candidate gene for polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age, and is characterized by infertility, hyperandrogenism and insulin resistance in skeletal muscle. There is evidence for a PCOS gene localized to chromosome 19p13.3. The FEMIA gene maps to chromosome 19p13.3 and is highly expressed in skeletal muscle. FEMIA is a homolog of fem-1, a sex-determination gene of Caenorhabditis elegans that controls masculinization. In a pilot study of Caucasian PCOS patients from our local clinic, we found that one of these five patients exhibited a heterozygous germline missense mutation in FEM1A, designated FEM1A*H500Y. This mutation alters an amino acid conserved from human to C. elegans, and was not found in any of 198 control chromosomes. This missense allele was not found in any of a separate group of 30 PCOS patients from a different regional/ethnic background. Immunostaining of mouse ovary demonstrated that the mouse homolog of FEM1A is expressed in androgen-producing secondary interstitial cells, with a marked increase in expression after puberty, consistent with a key feature of PCOS -- ovarian hyperandrogenism. In conclusion, FEM1A should be considered a candidate gene for PCOS, and more extensive analysis of FEM1A, both coding and regulatory sequences, is warranted in patients and families with PCOS.

Androgen excess fetal programming of female reproduction: a developmental aetiology for polycystic ovary syndrome?

The aetiology of polycystic ovary syndrome (PCOS) remains unknown. This familial syndrome is prevalent among reproductive-aged women and its inheritance indicates a dominant regulatory gene with incomplete penetrance. However, promising candidate genes have proven unreliable as markers for the PCOS phenotype. This lack of genetic linkage may represent both extreme heterogeneity of PCOS and difficulty in establishing a universally accepted PCOS diagnosis. Nevertheless, hyperandrogenism is one of the most consistently expressed PCOS traits. Animal models that mimic fetal androgen excess may thus provide unique insight into the origins of the PCOS syndrome. Many female mammals exposed to androgen excess in utero or during early post-natal life typically show masculinized and defeminized behaviour, ovulatory dysfunction and virilized genitalia, although behavioural and ovulatory dysfunction can coexist without virilized genitalia based upon the timing of androgen excess. One animal model shows particular relevance to PCOS: the prenatally androgenized female rhesus monkey. Females exposed to androgen excess early in gestation exhibit hyperandrogenism, oligomenorrhoea and enlarged, polyfollicular ovaries, in addition to LH hypersecretion, impaired embryo development, insulin resistance accompanying abdominal obesity, impaired insulin response to glucose and hyperlipidaemia. Female monkeys exposed to androgen excess late in gestation mimic these programmed changes, except for LH and insulin secretion defects. In utero androgen excess may thus variably perturb multiple organ system programming and thereby provide a single, fetal origin for a heterogeneous adult syndrome.

Evolving anticancer drug valproic acid: insights into the mechanism and clinical studies

The short chain fatty acid valproic acid (VPA) and VPA-analogs modulate the biology of diverse tumor cell entities by inducing differentiation, inhibiting proliferation, increasing apoptosis, and immunogenicity and by decreasing metastatic and angiogenetic potential. This review updates an earlier one in 2002, reflecting the interest in VPA as a potent anticancer drug. A number of in vitro studies show that the types of known tumor cells susceptible to VPA is steadily increasing. Of special note is the strong antineoplastic activity of VPA in chemoresistant cancer cells. A novel and promising approach is combining VPA with other drugs to achieve a broad therapeutic index. Clinical studies are underway and the preliminary results indicate that VPA alone or in combination offers a promising avenue of treatment, both in solid and hematopoetic malignancies.

Effects of dehydroepiandrosterone on ovarian cystogenesis and immune function

The purpose of the present report was to study the possible relationship between ovarian functionality and the immune response during cystogenesis induced by androgenization with dehydroepiandrosterone (DHEA). Daily injection of DHEA (6 mg/kg body weight) for 20 consecutive days induced ovarian cysts in BALB/c mice. As markers of ovarian function, serum estradiol (E) and progesterone (P) and the ovarian inmunomodulator prostaglandin E (PGE) were analyzed. In order to know how the integrity of the tissue was altered after induction of cystogenesis, the oxidative status was also evaluated. Serum E and P levels, and ovarian PGE concentration, were increased in animals with cysts compared with healthy controls. The oxidant status (quantified by malondialdehyde (MDA) formed after the breakdown of the cellular membrane by free radical mechanisms) was augmented, meanwhile the antioxidant (evaluated by the glutathione (GSH) content) diminished during the induction of cystogenesis. Both immunohistochemical and flow cytometry assays demonstrated that DHEA treatment increased the number of T lymphocytes infiltrating ovarian tissue. Therefore, while ovarian controls showed equivalent expression of CD4+ and CD8+ T cell subsets, injection of DHEA yielded a selective ovarian T cell infiltration as demonstrated by enhanced CD8+ and diminished CD4+ T lymphocyte expression. These results show that the development of cysts involves changes in ovarian function and an imbalance in the oxidant-antioxidant equilibrium. We observed also both an increased and selective T lymphocyte infiltration.

Dysregulation of cytochrome P450 17alpha-hydroxylase messenger ribonucleic acid stability in theca cells isolated from women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder characterized by ovarian hyperandrogenism. Theca interna cells isolated from the ovaries of women with PCOS are characterized by increased expression of cytochrome P450 17alpha-hydroxylase (CYP17) [steroid 17alpha-hydroxylase/17,20 lyase (P450c17)], a steroidogenic enzyme obligatory for the biosynthesis of androgens. Augmented expression of the gene encoding P450c17 (CYP17) in PCOS theca has been attributed, in part, to differential transcriptional regulation of the CYP17 promoter in normal and PCOS cells. The present studies examine whether CYP17 gene expression is also posttranscriptionally regulated at the level of mRNA stability in normal and PCOS theca cells maintained in long-term culture. Determination of endogenous CYP17 mRNA half-life by pharmacological inhibition of transcription demonstrated that the half-life of CYP17 mRNA increased 2-fold in PCOS theca cells, compared with normal theca cells. Forskolin treatment also prolonged CYP17 mRNA half-life in both normal and PCOS theca cells. In vitro mRNA degradation studies demonstrated that the 5'-untranslated region confers increased stability to CYP17 mRNA in PCOS theca cells and showed that the 5'-untranslated region of CYP17 also confers forskolin-stimulated stabilization of CYP17 mRNA. These studies indicate that a slower rate of CYP17 mRNA decay contributes to increased steady-state mRNA accumulation and augmented CYP17 gene expression in PCOS theca cells.

Genetics of polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is a reproductive system disorder characterized by irregular menses, anovulation, clinical and/or biochemical signs of hyperandrogenism (hirsutism and/or acne), ovarian micropolycystic appearance and metabolic abnormalities, such as hyperinsulinaemia and obesity. The aetiopathogenesis of this syndrome is not well known. Several pathogenetic hypotheses have been proposed to explain the full array of symptoms and signs, but with elusive results. A genetic abnormality causing PCOS is supported by the observation that different members of the same family are often affected, and about half of the sisters of PCOS women have elevated serum testosterone concentrations. Therefore, the presence of gene abnormalities in women with PCOS has been widely explored in the attempt to establish whether their mutations or polymorphisms may cause PCOS. The main genes evaluated are those involved in steroidogenesis, steroid hormone effects, gonadotrophin release regulation and action, insulin secretion and action, and adipose tissue metabolism. Despite the vast body of literature produced, none of the genes evaluated seems to play a key role in PCOS pathogenesis. It is likely that PCOS may represent the final outcome of different, deeply inter-related genetic abnormalities that influence each other and perpetuate the syndrome.

Alterations in mitogen-activated protein kinase kinase and extracellular regulated kinase signaling in theca cells contribute to excessive androgen production in polycystic ovary syndrome

We have investigated the involvement of the MAPK signaling pathway in increased androgen biosynthesis and CYP17 gene expression in women with polycystic ovary syndrome (PCOS). A comparison of MAPK kinase (MEK1/2) and ERK1/2 phosphorylation in propagated normal and PCOS theca cells, revealed that MEK1/2 phosphorylation was decreased more than 70%, and ERK1/2 phosphorylation was reduced 50% in PCOS cells as compared with normal cells. Infection with dominant-negative MEK1 increased CYP17 mRNA and dehydroepiandrosterone (DHEA) abundance, whereas constitutively active MEK1 reduced DHEA production and CYP17 mRNA abundance. Similarly, the MEK inhibitor, PD98059, increased CYP17 mRNA accumulation and CYP17 promoter activity to levels observed in PCOS cells. Remarkably, in theca cells maintained in the complete absence of insulin, ERK1/2 phosphorylation was decreased in PCOS theca cells as compared with normal theca cells, and CYP17 mRNA and DHEA synthesis were increased in PCOS theca cells. These studies demonstrate that in PCOS cells reduced levels of activated MEK1/2 and ERK1/2 are correlated with increased androgen production, irrespective of the insulin concentration. These findings implicate alterations in the MAPK pathway in the pathogenesis of excessive ovarian androgen production in PCOS.