Polycystic ovary syndrome resembling histopathological alterations in ovaries from prenatal androgenized female rats

Developmental programming: Impact of preconceptional and gestational exposure to a real-life environmental chemical mixture on maternal steroid, cytokine and oxidative stress milieus in sheep

BACKGROUND

Gestational exposure to environmental chemicals (ECs) is associated with adverse, sex-specific offspring health effects of global concern. As the maternal steroid, cytokine and oxidative stress milieus can have critical effects on pregnancy outcomes and the programming of diseases in offspring, it is important to study the impact of real-life EC exposure, i.e., chronic low levels of mixtures of ECs on these milieus. Sheep exposed to biosolids, derived from human waste, is an impactful model representing the ECs humans are exposed to in real-life. Offspring of sheep grazed on biosolids-treated pasture are characterized by reproductive and metabolic disruptions.

OBJECTIVE

To determine if biosolids exposure disrupts the maternal steroid, cytokine and oxidative stress milieus, in a fetal sex-specific manner.

METHODS

Ewes were maintained before mating and through gestation on pastures fertilized with biosolids (BTP), or inorganic fertilizer (Control). From maternal plasma collected mid-gestation, 19 steroids, 14 cytokines, 6 oxidative stress markers were quantified. Unpaired t-test and ANOVA were used to test for differences between control and BTP groups (n = 15/group) and between groups based on fetal sex, respectively. Correlation between the different markers was assessed by Spearman correlation.

RESULTS

Concentrations of the mineralocorticoids - deoxycorticosterone, corticosterone, the glucocorticoids - deoxycortisol, cortisol, cortisone, the sex steroids - androstenedione, dehydroepiandrosterone, 16-OH-progesterone and reactive oxygen metabolites were higher in the BTP ewes compared to Controls, while the proinflammatory cytokines IL-1β and IL-17A and anti-inflammatory IL-36RA were decreased in the BTP group. BTP ewes with a female fetus had lower levels of IP-10.

DISCUSSION

These findings suggest that pre-conceptional and gestational exposure to ECs in biosolids increases steroids, reactive oxygen metabolites and disrupts cytokines in maternal circulation, likely contributors to the aberrant phenotypic outcomes seen in offspring of BTP sheep - a translationally relevant precocial model.

Association of Oxidative Stress with Kidney Injury in a Hyperandrogenemic Female Rat Model

Background

Polycystic ovary syndrome (PCOS) is the most common reproductive dysfunction in premenopausal women. PCOS is associated with oxidative stress (OS), which is the main risk factor for renal diseases. This study aimed to investigate the mechanisms responsible for renal injury in a hyperandrogenemic female rat model.

Methods

This study was conducted from December 2019 to September 2021 at Shiraz Nephro-Urology Research Centre, Shiraz University of Medical Sciences (Shiraz, Iran). Thirty female Sprague-Dawley rats were randomly divided into three groups (n=10), namely control, sham, and dehydroepiandrosterone (DHEA). Plasma total testosterone, plasma creatinine (Cr), and blood urea nitrogen (BUN) levels were measured. In addition, total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI), and histopathological changes in the ovaries and kidneys were determined. Data were analyzed using the GraphPad Prism software, and P<0.05 was considered statistically significant.

Results

Plasma total testosterone levels increased by nine-fold in DHEA-treated rats compared to controls (P=0.0001). Administration of DHEA increased Cr and BUN levels and caused severe renal tubular cell injury. In addition, plasma and tissue (kidney and ovary) TAC levels decreased significantly, but TOS levels and OSI values were significantly increased (P=0.019). Significant damage to both glomerular and tubular parts of the kidney and ovarian follicular structure was observed in the DHEA group.

Conclusion

Hyperandrogenemia caused systemic abnormalities through OS-related mechanisms and damaged renal and ovarian tissues. DHEA treatment in rat models is recommended to study the mechanisms that mediate PCOS-associated renal injury.

Evaluation of the Effects of Caesalpinia crista on Letrozole-Induced Models of Polycystic Ovarian Syndrome

Background Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, affecting reproductive, endocrine, and metabolic functions. This study was designed to validate the claims in Ayurveda regarding the efficacy of Caesalpinia crista (Latakaranj) to treat PCOS. Its seeds are uterine stimulants and ovulation inducers and improve menstrual cycle irregularities. Objectives The present study aimed to evaluate the effects of Caesalpinia crista on reproductive abnormalities, reproductive hormones, and glycemic changes in a letrozole-induced model of PCOS. Material and methods The study was performed in rats with six groups having six rats in each group. The control group was given the vehicle carboxymethylcellulose (CMC) for 21 days orally, followed by normal saline (0.9% NaCl) orally for 15 days. The inducing agent, letrozole, was given to the disease control group and the four treatment groups for 21 days, followed by a treatment period of 15 days with either clomiphene citrate (1.8 mg/kg) orally in the clomiphene group, low-dose (100 mg/kg) Caesalpinia crista, medium-dose (300 mg/kg) Caesalpinia crista, or high-dose (500 mg/kg) Caesalpinia crista. The variables assessed were daily vaginal smears to check for estrous cyclicity, body weight, blood glucose, serum testosterone (T), serum luteinizing hormone (LH), serum follicle-stimulating hormone (FSH), and the number of oocytes from each oviduct. Histopathology of ovaries was also done. Result There was no significant difference between the different groups for body weight and blood glucose. There was a significant difference between the regularity of the estrous cycle of the disease control group and the high-dose Caesalpinia crista (500 mg/kg) group (p<0.01). Hormonal levels of luteinizing hormone (LH) (p<0.05) and follicle-stimulating hormone (FSH) (p<0.05) were significantly raised in the high-dose Caesalpinia crista group, and that of testosterone was significantly decreased (p<0.05) in the high-dose Caesalpinia crista group compared to the disease control group. The number of ova was significantly high in the high-dose Caesalpinia crista group compared to the disease control group (p<0.05). Decreased number of atretic follicles was seen in the high-dose and medium-dose Caesalpinia crista group on histopathology, with an increased number of corpus lutea (p<0.05). Conclusion Treatment with Caesalpinia crista in high dose, i.e., 500 mg/kg, significantly improved the reproductive abnormalities (ovulation and menstrual irregularities) and histopathological changes associated with PCOS. It also restored reproductive hormone levels (testosterone, FSH, and LH), which are elevated in PCOS, and normalized the LH/FSH ratio, which is deranged in PCOS.

Investigation of the effects of astaxanthin in experimental polycystic ovary syndrome (PCOS) in rats

Objectives

The aim of this study was to investigate the effect of Astaxanthin (ASX) on ovaries in letrozole-induced polycystic ovary syndrome (PCOS) model in female rats by histopathological, immunohistochemical and biochemical techniques.

Materials and Methods

Seventy two Sprague-Dawley female rats with an average weight of 200-250 gr and 10-12 weeks old were randomly divided into 9 groups. PCOS model was applied to all groups except healthy group. In the study, low (10 mg / kg) moderate (20 mg / kg) and high (40 mg / kg) doses of ASX were given to the experimental animals in the PCOS-induced groups for 7 days. At the end of the experiment, ovarian tissues were evaluated histopathologically, immunohistochemically, and biochemically.

Results

When the histopathological findings were examined, many cystic follicles, apoptotic and necrotic cells were found in the follicles in the PCOS group. In addition, significant decrease in apoptotic and necrotic cells were observed in PCOS+MET+ASX and PCOS+ASX groups. In immunohistochemical staining findings, while TNF-α NF-κB and IL-6 expression levels showed significant increase in PCOS group, these expression levels were decreased in PCOS+MET+ASX and PCOS+ASX groups. In the biochemical evaluations, while MDA were increased, SOD were decreased in the PCOS group. MDA level were decreased while SOD levels were increased in the PCOS+MET+ASX and PCOS+ASX groups.

Conclusion

In addition to the formation of insulin resistance in the tissue, severe oxidative stress damage occurs in ovarian tissue during PCOS. Metformin improved PCOS by correcting insulin resistance. In this period, the administration of ASX with Metformin protected the ovary from oxidative stress damage.

Development and evaluation of novel rodent model of PCOS mimicking clinical phenotype in human disease

Background

Polycystic ovary syndrome is a most common female reproductive disorder, involving endocrine and metabolic disorders with unclear etiology. Androgen-based rodent animal models like DHEA and DHT are most suitable for PCOS induction, but still, these models fail to produce non-lean PCOS phenotypes such as hyperandrogenism, hyperinsulinemia, elevated estrogen levels, and ovary weight. Excess fructose consumption leads to hyperandrogenism, hyperinsulinemia, and insulin resistance. The purpose of this study is to investigate, whether fructose consumption along with androgens in rats, could develop all metabolic and endocrine phenotypes of non-lean human PCOS disease. 

Methods

Prepubertal SD rats were administered with DHT (83ug, s.c.) and fructose (20%, p.o.) for 90 days whereas DHEA (7 mg/kg, s.c) and fructose (20%, p.o.) for 30 days. During study duration, the blood glucose level for oral glucose tolerance test, estrus cyclicity, and ultrasonography was observed. Reproductive hormones LH, FSH, insulin, testosterone, and estradiol levels were assessed using ELISA. The ovary, uterus, abdominal fat, and subcutaneous fat were collected and weighed, and histopathology was done for any anomaly’s findings.

Results

DHT + fructose-treated rats showed significant (p < 0.05) increase in serum testosterone, LH, estradiol, decreased FSH levels, and caused multiple cystic follicles. Abdominal fat, subcutaneous fat, ovary, and uterine weight were higher in DHT + F and DHEA + F when compared to control groups. OGTT reveals impaired insulin sensitivity and glucose tolerance in both model groups. Ovarian histopathology of DHT + F shows more cysts than the DHEA + F groups. No significant changes in uterine histology of DHT + F and DHEA + F-treated rats.

Conclusion

DHT + F-treated rats mimic all clinical phenotypes and could be used as novel rodent model for non-lean type PCOS.

Polycystic Ovarian Syndrome: A Complex Disease with a Genetics Approach

Polycystic ovarian syndrome (PCOS) is a complex endocrine disorder affecting females in their reproductive age. The early diagnosis of PCOS is complicated and complex due to overlapping symptoms of this disease. The most accepted diagnostic approach today is the Rotterdam Consensus (2003), which supports the positive diagnosis of PCOS when patients present two out of the following three symptoms: biochemical and clinical signs of hyperandrogenism, oligo, and anovulation, also polycystic ovarian morphology on sonography. Genetic variance, epigenetic changes, and disturbed lifestyle lead to the development of pathophysiological disturbances, which include hyperandrogenism, insulin resistance, and chronic inflammation in PCOS females. At the molecular level, different proteins and molecular and signaling pathways are involved in disease progression, which leads to the failure of a single genetic diagnostic approach. The genetic approach to elucidate the mechanism of pathogenesis of PCOS was recently developed, whereby four phenotypic variances of PCOS categorize PCOS patients into classic, ovulatory, and non-hyperandrogenic types. Genetic studies help to identify the root cause for the development of this PCOS. PCOS genetic inheritance is autosomal dominant but the latest investigations revealed it as a multigene origin disease. Different genetic loci and specific genes have been identified so far as being associated with this disease. Genome-wide association studies (GWAS) and related genetic studies have changed the scenario for the diagnosis and treatment of this reproductive and metabolic condition known as PCOS. This review article briefly discusses different genes associated directly or indirectly with disease development and progression.

Recent updates on animal models for understanding the etiopathogenesis of polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is the primary cause of female infertility affecting several women worldwide. Changes in hormonal functions such as hyperandrogenism are considered a significant factor in developing PCOS in women. In addition, many molecular pathways are involved in the pathogenesis of PCOS in women. To have better insights about PCOS, it is data from clinical studies carried on women suffering from PCOS should be collected. However, this approach has several implications, including ethical considerations, cost involved and availability of subject. Moreover, during the early drug development process, it is always advisable to use non-human models mimicking human physiology as they are less expensive, readily available, have a shorter gestation period and less risk involved. Many animal models have been reported that resemble the PCOS pathways in human subjects. However, the models developed on rats and mice are more preferred over other rodent/non-rodent models due to their closer resemblance with human PCOS development mechanism. The most extensively reported PCOS models for rats and mice include those induced by using testosterone, letrozole and estradiol valerate. As the pathophysiology of PCOS is complex, none of the explored models completely surrogates the PCOS related conditions occurring in women. Hence, there is a need to develop an animal model that can resemble the pathophysiology of PCOS in women. The review focuses on various animal models explored to understand the pathophysiology of PCOS. The article also highlights some environmental and food-related models that have been used to induce PCOS.

Potential of Auraptene in Improvement of Oocyte Maturation, Fertilization Rate, and Inflammation in Polycystic Ovary Syndrome Mouse Model

Polycystic ovary with poor-quality oocytes has remained problematic in polycystic ovary syndrome (PCOS) patients. It is well documented that the inflammation and production of reactive oxygen species (ROS) in PCOS ovaries are significantly higher than normal voluntaries. In this study, we hypothesized that auraptene (AUR), as a coumarin derivative with anti-inflammatory properties, may be effective in improvement of oocyte maturation and fertilization rate in PCOS patients. For this purpose, PCOS model was induced in NMRI mice and confirmed by ovarian histopathology observations and hormonal assays. PCOS-induced mice were administrated with AUR (PCOS-AUR) and metformin (PCOS-MET), and their effects on inflammation, apoptosis rate, oocyte maturation, and in vitro fertilization capacity were determined and compared with those normal and PCOS animals treated with sesame oil (PCOS-sesame oil) and no treatment (PCOS). Treatment with AUR and MET decreased the inflammation and apoptosis rates in PCOS mice compared with PCOS animals with no treatment. PCOS-AUR and PCOS-MET oocytes also showed higher intracellular glutathione and lower ROS concentrations compared with PCOS mice, indicating improved oocyte maturation rate. PCOS-AUR and PCOS-MET groups showed higher percentages of expansion rate and MII stage oocytes, and lower rate of abnormal oocytes compared with PCOS with no treatment. The rate of fertilization in the oocytes isolated from PCOS-AUR and PCOS-MET groups was higher than PCOS-sesame oil and PCOS groups. Our findings suggest that AUR can be considered as a potential candidate for improvement of oocyte maturation and fertilization capacity in PCOS patients, comparable to MET.

Quercetin and polycystic ovary syndrome, current evidence and future directions: a systematic review

Polycystic ovary syndrome (PCOS) is a polygenic endocrine disorder and the most common gynecological endocrinopathy among reproductive-aged women. Current remedies are often used only to control its signs and symptoms, while they are not thoroughly able to prevent complications. Quercetin is an herbal bioactive flavonoid commonly used for the treatment of metabolic and inflammatory disorders. Thus, this systematic review was conducted to evaluate the efficacy of quercetin supplementation in subjects with PCOS. Databases until March 2019 were searched. All human clinical trials and animal models evaluating the effects of quercetin on PCOS women were included. Out of 253 articles identified in our search, 8 eligible articles (5 animal studies and 3 clinical trials) were reviewed. The majority of studies supported the beneficial effects of quercetin on the ovarian histomorphology, folliculogenesis, and luteinisation processes. The effects of quercetin on reducing the levels of testosterone, luteinizing hormone (LH), and insulin resistance were also reported. Although quercetin improved dyslipidemia, no significant effect was reported for weight loss. It is suggested that the benefits of quercetin may be more closely related to antioxidant and anti-inflammatory features of quercetin rather than weight-reducing effects. Therefore, this review article provides evidence that quercetin could be considered as a potential agent to attenuate PCOS complications. However, due to the paucity of high-quality clinical trials, further studies are needed.

Genetic Basis of Polycystic Ovary Syndrome (PCOS): Current Perspectives

Polycystic ovary syndrome (PCOS) is a common infertility disorder affecting a significant proportion of the global population. It is the main cause of anovulatory infertility in women and is the most common endocrinopathy affecting reproductive-aged women, with a prevalence of 8-13% depending on the criteria used and population studied. The disease is multifactorial and complex and, therefore, often difficult to diagnose due to overlapping symptoms. Multiple etiological factors have been implicated in PCOS. Due to the complex pathophysiology involving multiple pathways and proteins, single genetic diagnostic tests cannot be determined. Progress has been achieved in the management and diagnosis of PCOS; however, not much is known about the molecular players and signaling pathways underlying it. Conclusively PCOS is a polygenic and multifactorial syndromic disorder. Many genes have been associated with PCOS, which affect fertility either directly or indirectly. However, studies conducted on PCOS patients from multiple families failed to find a fully penetrant variant(s). The present study was designed to review the current genetic understanding of the disease. In the present review, we have discussed the clinical spectrum, the genetics, and the variants identified as being associated with PCOS. The mechanisms by which variants in the genes confer risk to PCOS and the nature of the physical and genetic interaction between the genetic elements underlying PCOS remain to be determined. Elucidation of genetic players and cellular pathways underlying PCOS will certainly increase our understanding of the pathophysiology of this syndrome. The study also discusses the current status of the treatment modalities for PCOS, which is important to find new ways of treatment.

Animal models of polycystic ovary syndrome: A review of hormone-induced rodent models focused on hypothalamus-pituitary-ovary axis and neuropeptides

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder among women of reproductive age and a major cause of infertility; however, the pathophysiology of this syndrome is not fully understood. This can be addressed using appropriate animal models of PCOS. In this review, we describe rodent models of hormone-induced PCOS that focus on the perturbation of the hypothalamic-pituitary-ovary (HPO) axis and abnormalities in neuropeptide levels.

METHODS

Comparison of rodent models of hormone-induced PCOS.

MAIN FINDINGS

The main method used to generate rodent models of PCOS was subcutaneous injection or implantation of androgens, estrogens, antiprogestin, or aromatase inhibitor. Androgens were administered to animals pre- or postnatally. Alterations in the levels of kisspeptin and related molecules have been reported in these models.

CONCLUSION

The most appropriate model for the research objective and hypothesis should be established. Dysregulation of the HPO axis followed by elevated serum luteinizing hormone levels, hyperandrogenism, and metabolic disturbance contribute to the complex etiology of PCOS. These phenotypes of the human disease are recapitulated in hormone-induced PCOS models. Thus, evidence from animal models can help to clarify the pathophysiology of PCOS.

Effect of Vitex negundo L. seeds in letrozole induced polycystic ovarian syndrome

The clinical management of PCOS is multifaceted but often unsatisfactory. The aim of the current study is to evaluate the effect of Vitex negundo L. in the letrozole-induced polycystic ovarian syndrome. Female Sprague-Dawley rats were divided into six groups, each containing 6 animals. Group I (Control) daily received 1% carboxymethylcellulose (CMC) suspension as a vehicle control. Letrozole (1 mg/kg) was administered per orally (p.o) for a period of 21 days for the induction of PCOS in Group II to VI. PCOS induced animals were treated with aqueous (Group III - 200 mg/kg and IV- 400 mg/kg) and hydroalcoholic extract (Group V- 200 mg/kg and VI- 400 mg/kg) of Vitex negundo up to 66 days using 0.5% w/v CMC as the vehicle. Body weight and estrous cycle phase were measured every day. Blood samples were collected on 0, 21 and 66 days for the measurement of fasting blood glucose, lipid profile, LH, FSH and hormonal level. Oral glucose tolerance test was performed to study insulin resistance effect. Toxicity markers; SGOT, SGPT, and creatinine also measured at the end of the study. The administration of Letrozole led to an abnormality in serum sex steroid profile, lipid profile, glucose and estrous cycle. It was able to successfully exert its protective effect by restoring parameters to the normal level and disappearance of cysts in ovaries. This can be attributed to phyto-components present in the extract. The aqueous and hydro-alcoholic extracts of seeds of Vitex negundo showed significant amelioration of Letrozole induced PCOS.

Effect of resveratrol and metformin on ovarian reserve and ultrastructure in PCOS: an experimental study

Background

PCOS is a reproductive hormonal abnormality and a metabolic disorder. It is frequently associated with insulin resistance, hyperandrogenism, chronic inflammation, and oxidative stress. We aim to investigate the potential therapeutic effects of combined therapy of resveratrol and metformin on polycystic ovaries via SIRT1 and AMPK activation.

Methods

Wistar albino rats were divided into control and experimental (PCOS) groups. DHEA-induced PCOS rats were given resveratrol (20 mg/kg/day), metformin (300 mg/kg/day) and combined therapy. At the end of the experiment, the body and ovarian weight of rats were measured and blood samples were analyzed for FSH, LH, testosterone, AMH, TNF-α and MDA levels. Histopathological evaluation of ovaries were carried out by light and electron microscopy. SIRT1 and AMPK immunreactivity and TUNEL assay were scored. Data were statistically analyzed by SPSS programme.

Results

Metformin and combined treatment groups reduced the body and ovary weights compared to the PCOS group. Serum testosterone levels were significantly higher in the PCOS group than in the control group and this was reduced when PCOS was treated with all but especially resveratrol. All the treatment groups decreased LH, LH/FSH, TNF-α and tissue AMH levels which were induced in the PCOS group, whereas metformin was unable to improve the increased MDA and plasma AMH levels. Treatment with resveratrol and/or metformin ameliorated the elevated number of secondary and atretic follicles and the decreased number of Graafian follicles in the PCOS group, which indicates the effect of the treatments on the maintenance of folliculogenesis. Light and electron microscopic findings supported the analysis of follicular count. Increased number of TUNEL (+) granulosa cells in the PCOS group were reduced significantly in the treatment groups. Resveratrol and metformin increased SIRT1 and AMPK immunreactivity, respectively, compared to the PCOS group.

Conclusions

The results suggest that combined therapy of metformin and resveratrol may improve the weight gain, hormone profile and ovarian follicular cell architecture by inducing antioxidant and antiinflammatory systems via SIRT1 and AMPK activation in PCOS.

GDF9 and BMP15 Expressions and Fine Structure Changes During Folliculogenesis in Polycystic Ovary Syndrome

Background:

Polycystic ovary syndrome is the most frequently seen endocrine disorder in women of reproductive age with a prevalence of about 10%.

Aims:

To investigate the efficiency of growth differentiation factor 9 and bone morphogenetic protein 15 during folliculogenesis in a dehydroepiandrosterone-induced mouse Polycystic ovary syndrome model.

Study Design:

Animal experimentation.

Methods:

Mice were divided into 3 groups: control, vehicle and Polycystic ovary syndrome. Polycystic ovary syndrome model mice were developed by the injection of dehydroepiandrosterone dissolved in 0.1 mL of sesame oil. Ovarian tissues were examined for growth differentiation factor 9 and bone morphogenetic protein 15 using immunofluorescent labelling and electron microscopic examinations.

Results:

The immunoreactivity of growth differentiation factor 9 and bone morphogenetic protein 15 proteins decreased (p<0.05) in the Polycystic ovary syndrome group (27.73±8.43 and 24.85±7.03, respectively) compared with the control group (33.72±11.22 and 31.12±11.05, respectively) and vehicle group (33.95±10.75 and 29.99±10.72, respectively). Apoptotic changes were observed in granulosa cells, lipid vacuoles increased in Theca cells and thickening and irregularities were noted in the basal lamina of granulosa cells. An increased electron density in the zona pellucida in some of the multilaminar primary and secondary follicles in the Polycystic ovary syndrome model was also observed at the ultrastructural level.

Conclusion:

These results suggest that the decrease in the growth differentiation factor 9 and bone morphogenetic protein 15 expression initiated at the primary follicle stage effect the follicle development and zona pellucida structure and may cause subfertility or infertility in Polycystic ovary syndrome.

Current aspects of polycystic ovary syndrome: A literature review

SUMMARY Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder with variable prevalence, affecting about one in every 15 women worldwide. The diagnosis of polycystic ovary syndrome requires at least two of the following criteria: oligoovulation and/or anovulation, clinical and/or biochemical evidence of hyperandrogenism and morphology of polycystic ovaries. Women with PCOS appear to have a higher risk of developing metabolic disorders, hypertension and cardiovascular disorders. The aim of this article was to present a review of the literature by searching the databases Pubmed and Scielo, focusing on publications related to polycystic ovaries, including its pathogenesis, clinical manifestations, diagnosis and therapeutic aspects, as well as its association with cardiovascular and arterial hypertensive disorders.

The epigenomics of polycystic ovarian syndrome: from pathogenesis to clinical manifestations

Polycystic ovarian syndrome (PCOS) is a complex condition of ovarian dysfunction and metabolic abnormalities with widely varying clinical manifestations resulting from interference of the genome and the environment through integrative biological mechanisms with the emerging field of epigenetics offering an appealing tool for studying the nature and nurture of the disease. We review the current literature of epigenetic studies on PCOS from disease development to the association analysis of the DNA methylome and to exploratory studies on the molecular mechanisms of disease heterogeneity and comorbidity. Recent data based on profiling of the DNA methylome of PCOS in different tissues provided consistent molecular evidence in support of epidemiological findings on disease comorbidity suggesting a possible autoimmune basis in the pathogenesis of the disease. We show that the field of epigenetics and epigenomics could serve to link molecular regulatory mechanisms with disease development and disease manifestation which could contribute to PCOS prevention and treatment and eventually promote reproductive health in fertile age women. We summarize the up-to-date findings and discuss the implications of various studies and point to new avenues of research on PCOS in the rapidly developing field of epigenetics and epigenomics.

Phosphatidylinositide 3-kinase inhibition: A new potential target for the treatment of polycystic ovarian syndrome

CONTEXT

Quercetin, a flavonoid, has been tried in traditional medicine for treating many disorders and reported to have inhibitory action on PI3 kinase.

OBJECTIVE

This study investigates the effect of quercetin on testosterone propionate induced polycystic ovary syndrome (PCOS) model, which shows both metabolic and endocrine features of PCOS.

MATERIALS AND METHODS

Female pre-pubertal Sprague-Dawley rats were randomly divided into four groups: normal control, PCOS control, quercetin, and metformin treated. PCOS was induced by testosterone propionate (10 mg/kg, s.c.) and treatments were carried out orally at the dose of 150 mg/kg from the 6th week. At the 6th and 10th week, blood was collected to investigate metabolic indices, and reproductive biochemical parameters including morphology of ovary, uterus, and estrous cyclicity were assessed. The ovaries were processed to determine CYP17A1 gene expression.

RESULTS

The treatment with quercetin did not modify body weight gain but uterine (296.7 ± 5.11 versus 263.0 ± 8.60 mg) and ovary weights (49.5 ± 1.93 versus 37.8 ± 3.43 mg) were found to be decreased significantly (p <0.05) as compared with the PCOS control group. The PCOS control group showed hyperinsulinemia, hyperandrogenemia, and dyslipidemia. Treatment with quercetin showed statistically significant (p <0.01) improvement in insulin (12.46 ± 0.3 versus 10.0 ± 0.28 μU/ml), testosterone (0.65 ± 0.02 versus 0.29 ± 0.02 μU/ml), luteinising hormone (20.6 ± 0.28 versus 15.1 ± 0.36 U/ml), and lipid profile. Histological examination of ovary and uterus confirmed the disease occurrence and remission state in the diseased and treated groups, respectively. Quercetin also demonstrated PI3 kinase inhibition in a docking study and decreased CYP17A1 gene expression.

DISCUSSION AND CONCLUSION

Thus, we can conclude that quercetin may have beneficial effect in PCOS by virtue of inhibition of PI3K which attributes to a decrease in the expression of CYP17A1 gene, having a key role in steroidogenesis.

Antimullerian hormone and its receptor gene expression in prenatally androgenized female rats

BACKGROUND

Anti-mullerian hormone (AMH) levels reflect the number of small antral follicles in ovaries and expression changes of AMH and its receptor are suspected to be involved in the pathogenesis of polycystic ovary syndrome (PCOS).

OBJECTIVES

The aim of this study was to evaluate gene expression of AMH and its receptor in immature and adult rats prenatally exposed to androgen excess.

MATERIALS AND METHODS

Six pregnant Wistar rats in the experimental group were treated by subcutaneous injection of 5 mg free testosterone on day 20 of pregnancy, while controls (n = 6) received only 500 mL of solvent. Female pups of each mother were randomly divided into three groups as day 0 (newborn), 10-day old and days 75-85 (adult). RNAs were extracted from ovarian tissues and relative expression levels for AMH and its receptor genes were measured using TaqMan Real-Time PCR. Serum AMH and testosterone levels were measured using ELISA method.

RESULTS

Relative AMH expression decreased in newborns, 10-day olds and adults (0.806, 0.443 and 0.809 fold, respectively). AMHR expression was higher in newborns and adults (1.432 and 1.057 fold, respectively), while it decreased by 0.263 fold in 10-day olds, although none of them were significant (P > 0.05). In addition, AMH levels were consistent with the results of gene expression. Testosterone hormone levels from 10 day-olds to adults were significantly increased in both study groups (P = 0.016).

CONCLUSIONS

While AMH receptor expression was higher in experimental rats, their serum concentrations of AMH were decreased. Further researches with greater sample sizes and measurement of bioactive forms of hormones are recommended to confirm the findings of this study.

Nonproliferative and proliferative lesions of the rat and mouse female reproductive system

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) Project (www.toxpath.org/inhand.asp) is a joint initiative of the Societies of Toxicological Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in the female reproductive tract of laboratory rats and mice, with color photomicrographs illustrating examples of some lesions. The standardized nomenclature presented in this document is also available electronically on the internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and aging lesions as well as lesions induced by exposure to test materials. There is also a section on normal cyclical changes observed in the ovary, uterus, cervix and vagina to compare normal physiological changes with pathological lesions. A widely accepted and utilized international harmonization of nomenclature for female reproductive tract lesions in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.