Immunohistochemical evaluation of proliferation, apoptosis and steroidogenic enzymes in the ovary of rats with polycystic ovary

Comparative analysis of oral and local intraovarian administration of metformin and nanoparticles (NPs11) in alleviating testosterone-induced polycystic ovary syndrome in rats

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic dysfunction. This study aims to compare the oral and local treatments of metformin or its nanoparticles (NPs11) for ameliorating PCOS in rats. Rats were divided into 4 groups: the control group with no drug treatment; the PCOS group, where subcutaneous testosterone was given (10 mg/kg/day) for 28 days; the MET group, where metformin was administered orally or locally; and the NP group, where metformin NPs11 were also administered orally or locally. Oral administrations were for 21 days, while local injection was performed once surgically. After 7 weeks, all rats were sacrificed; blood glucose and serum hormonal levels and lipid profile were estimated, and the ovaries were assessed by histopathological, Ki-67 immunohistochemical, and histomorphometric evaluations. Blood glucose levels were significantly decreased in groups of orally administered metformin or NPs11 only, while the most efficient option for modulating PCOS-induced hormonal and lipid profile changes was intraovarian injection of NPs11. The ovaries of PCOS rats demonstrated large follicular cysts, massive collagen depositions, and attenuated Ki-67 immunoexpression. Also, the PCOS group revealed a significant decrease in the count of all stages of growing follicles, corpora lutea, granulosa cell layer thickness, and surface area of corpora lutea, in addition to an increase in the number of atretic follicles and follicular cysts, theca cell layer thickness, and surface area of the follicular cysts. All these parameters were recovered with metformin or their NPs11 treatments in different degrees, while local injection of NPs11 was the best option.

Effects of melatonin and metformin on the ovaries of rats with polycystic ovary syndrome

OBJECTIVE

To study the combined and isolated effects of melatonin and metformin in the ovarian tissue of rats with PCOS.

DESIGN

Experimental study using a rat model of PCOS induced by continuous light exposure.

INTERVENTION(S)

Forty adult female rats were divided into 5 groups: physiological estrus phase (Sham); permanente estrus with PCOS induced by continuous lighting exposure for 60 consecutive days (control); with PCOS treated with melatonin; with PCOS treated with metformin; with PCOS treated with melatonin + metformin. After 60 days of treatments, all rats were killed, and ovaries were collected and processed for paraffin-embedding. Formalin-fixed paraffin-embedded sections were stained with hematoxylin and eosin or subjected to immunohistochemistry for proliferation (Ki-67) and apoptosis (cleaved caspase 3) detection markers.

SETTING

Federal University of São Paulo, Brazil.

ANIMALS

Forty adult female Wistar rats (Rattus norvegicus albinus).

MAIN OUTCOME MEASURE(S)

Number of corpus luteum and ovarian cysts, number of ovarian follicles (primary and antral follicles), number of interstitial cells, percentage of ovarian follicles (primary and antral follicles), and of interstitial cells immunostained to cleaved caspase-3 and Ki-67.

RESULTS

Absence of corpus luteum, a higher number of cysts, and increased nuclear volume and area of interstitial cells, along with a decrease in primary and antral follicle numbers, were noticed in the control group compared with the Sham group. Melatonin and metformin treatments attenuated these effects, although the combined treatment did not mitigate the increased number of cysts and ovaries induced by PCOS. An increase in theca interna cell apoptosis was observed in the control group, whereas melatonina and metformin treatments reduced it significantly. A higher percentage of caspase-3-immunostained granulosa cells was noted in the Sham and all treated groups compared with the control group; no aditive effects on ovarian cell apoptosis were observed in the combined treatment. The percentage of Ki-67- immunostained granulosa cells was significantly higher in the control group compared with the Sham group. However, the combined treatment, not melatonin and metformin alone, mitigated this effect. A higher percentage of Ki-67-immunostained interstitial cells was observed in all treated groups compared with the Sham and control groups, whereas no additive effects in that immunoreactivity were observed in the combined treatment.

CONCLUSIONS

Melatonin and metformin may improve ovarian function in rats with PCOS. The combined melatonin and metformin treatment is more effective in attenuating excessive granulosa cell proliferation, but it is not more effective in improving ovarian function than these drugs applied alone in rats with PCOS.

Novel insights into the synergistic effects of selenium nanoparticles and metformin treatment of letrozole - induced polycystic ovarian syndrome: targeting PI3K/Akt signalling pathway, redox status and mitochondrial dysfunction in ovarian tissue

PURPOSE

Polycystic ovary syndrome (PCOS) has a series of reproductive and metabolic consequences. Although the link between PCOS, IR, and obesity, their impact on the pathogenesis of PCOS has yet to be determined. Dysfunction of PI3K/AKT pathway has been reported as the main cause of IR in PCOS. This study purposed to explore the effects of selenium nanoparticles (SeNPs) alone and combined with metformin (MET) in a PCOS-IR rat model.

METHODS

After 3 weeks of treatment with SeNPs and/or MET, biochemical analysis of glycemic & lipid profiles, and serum reproductive hormones was performed. Inflammatory, oxidative stress, and mitochondrial dysfunction markers were determined colormetrically. The expression of PI3K and Akt genes were evaluated by Real-time PCR. Histopathological examination and Immunohistochemical analysis of Ki-67 expression were performed.

RESULTS

The results showed that treatment with SeNPs and/or MET significantly attenuated insulin sensitivity, lipid profile, sex hormones levels, inflammatory, oxidative stress and mitochondrial functions markers. Additionally, PI3K and Akt genes expression were significantly upregulated with improved ovarian histopathological changes.

CONCLUSION

Combined SeNPs and MET therapy could be potential therapeutic agent for PCOS-IR model via modulation of the PI3K/Akt pathway, enhancing anti-inflammatory and anti-oxidant properties and altered mitochondrial functions.

HighlightsThe strong relationship between obesity, insulin resistance, and polycystic ovarian syndrome.Disturbance of the PI3K/Akt signaling pathway is involved in the progression of polycystic ovary syndrome-insulin resistance (PCOS-IR).In PCOS-IR rats, combined SeNPs and metformin therapy considerably alleviated IR by acting on the PI3K/Akt signaling pathway.The combination of SeNPs and metformin clearly repaired ovarian polycystic pathogenesis and improved hormonal imbalance in PCOS-IR rats.

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

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

Follicular Atresia, Cell Proliferation, and Anti-Mullerian Hormone in Two Neotropical Primates (Aotus nancymae and Sapajus macrocephalus)

This study evaluated the follicular atresia, cell proliferation, and anti-Mullerian hormone action in Aotus nancymae and Sapajus macrocephalus during three sexual phases (follicular, luteal, and gestational). Follicular quantification and immunolocalization of Caspase-3 protein, B-cell lymphoma 2 (BCL-2), proliferating cell nuclear antigen (PCNA), and anti-Mullerian hormone (AMH) were performed. A significant difference in the quantification between preantral and antral follicles, with a progressive decrease in the antrals, was identified. Protein and hormonal markers varied significantly between follicle cell types (A. nancymae p = 0.001; S. macrocephalus, p = 0.002). Immunostaining in the preantral and antral follicles was present in all sexual phases; for Caspase-3, in granulosa cells, oocytes, and stroma; for BCL-2, in granulosa cells, oocytes, and theca; and for PCNA and AMH, in oocytes and granulosa cells. The immunostaining for Caspase-3 was more expressive in the preantral follicles (follicular phase, p < 0.05), while that for BCL-2 and PCNA was more expressive in the antral follicles of the follicular phase. The AMH was more expressive in the primary and antral follicles of nonpregnant females, in both the follicular and luteal phases. Our results contribute to understanding the ovarian follicular selection, recruitment, and degeneration of these species.

Administration of hemin ameliorates ovarian ischemia reperfusion injury via modulation of heme oxygenase-1 and p-JNK/p-NF-κBp65/iNOS signaling pathway

AIMS

Ovarian torsion is the fifth common gynecological emergency that can affect females of all ages particularly during reproductive age and its management by detorsion leads to ovarian ischemia reperfusion (IR) injury. Therefore, prophylactic measures are required to protect the ovarian function after detorsion. So that, our study aimed to assess the effect and underlying mechanisms of heme oxygenase-1 (HO-1) inducer; hemin against ovarian damage induced by IR injury in rats.

MAIN METHODS

Female rats were divided into: sham group, hemin group, ovarian IR (OIR) groups with and without hemin treatment. Serum levels of reduced glutathione (GSH) and interleukin 1 β (IL-1β) were measured in addition to ovarian levels of malondialdehyde (MDA), nitric oxide (NO) and superoxide dismutase (SOD). Ovarian phospho-Janus kinase (p-JNK) levels and gene expressions of HO-1 and inducible nitric oxide synthase (iNOS) were determined. Moreover, histopathological changes and expressions of phospho-nuclear factor kappa B p65 (p-NF-κB p65) and cleaved caspase-3 were done.

KEY FINDINGS

Treatment of OIR rats with hemin led to significant attenuation of ovarian damage through histological examination which was associated with significant increase in ovarian expression of HO-1, ovarian SOD and serum GSH levels with significant decrease in ovarian p-JNK levels, expressions of p-NF-κB p65, iNOS and cleaved caspase-3 in addition to serum IL-1β levels.

SIGNIFICANCE

The protective effect of hemin can be attributed to the increased expression of HO-1 which showed antioxidant, anti-inflammatory and anti-apoptotic effects. Therefore, hemin can be administered to prevent ovarian IR injury which occurs after detorsion.

Therapeutic Effect of P-Cymene on Lipid Profile, Liver Enzyme, and Akt/Mtor Pathway in Streptozotocin-Induced Diabetes Mellitus in Wistar Rats

Diabetes is a serious public health problem in low- and middle-income countries. There is a strong link between hyperglycemia, oxidative stress, inflammation, and the development of diabetes mellitus. PI3K/Akt/mTOR is the main signaling pathway of insulin for controlling lipid and glucose metabolism. P-cymene is an aromatic monoterpene with a widespread range of therapeutic properties including antioxidant and anti-inflammatory activity. In the present study, the antidiabetic effects of p-cymene were investigated. Diabetes was induced using streptozotocin in male Wistar rats. The effects of p-cymene and metformin were studied on levels of glucose (Glu), lipid profile, liver enzymes, oxidative stress, and the expression of Akt, phospho-Akt, and mTOR (mammalian target of rapamycin) proteins, using biochemical, histological, and immunohistochemical analysis. Data have shown that p-cymene can improve serum levels of Glu, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL), alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), and the expression of mTOR, Akt, and phospho-Akt protein in diabetic animals. These results suggest that p-cymene has hypoglycemia, hypolipidemia, and antioxidant properties. It can regulate Akt/mTOR pathway and reduce hepatic and pancreas injury. It can be suggested for diabetes management alone or simultaneously with metformin.

Histomorphometric and immunohistochemical changes in interstitial cells and ovarian follicles of rats with polycystic ovaries treated with clomiphene citrate

OBJECTIVE

To evaluate the histomorphometric and immunohistochemical changes in interstitial cells and ovarian follicles of rats treated with clomiphene citrate during and after induction of permanent estrus.

METHODS

Twenty four adult-female rats with regular estrous cycle were equally divided into three groups: (1) GCtrl-at estrous phase. (2) GPCOS-at permanent-estrous phase. (3) GCC-PCOS rats, which remained exposed to 60 days of continuous illumination and treated with Clomiphene Citrate. After that, the animals were euthanized, and the ovaries were removed and processed for paraffin embedding. Sections were stained with H.E. for histomorphometry or subjected to immunohistochemistry for Ki-67 and cleaved caspase-3 detections.

RESULTS

The GPCOS showed lack of corpus luteum and several ovarian cysts, as well as interstitial-like cells. The presence of corpus luteum and a significant increase in primary and antral follicles were observed in GCC, which also showed a decrease in the number of ovarian cysts and in the area occupied by interstitial-like cells, as well as a decrease in nuclear volume of interstitial cells. The percentage of cell proliferation was significantly higher in granulosa cells of the GCC. On the other hand, the percentage of apoptosis was significantly higher in the granulosa cells of GPCOS than the GCC.

CONCLUSION

The ovaries of rats treated with clomiphene citrate showed a decrease in the number of cysts, an increase in the number of ovarian follicles, the presence of corpus luteum along with a decrease in the nuclear volume in the area occupied by interstitial cells.

Identification of Crucial lncRNAs, miRNAs, mRNAs, and Potential Therapeutic Compounds for Polycystic Ovary Syndrome by Bioinformatics Analysis

BACKGROUND

This study was aimed at mining crucial long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and messenger RNAs (mRNAs) for the development of polycystic ovary syndrome (PCOS) based on the coexpression and the competitive endogenous RNA (ceRNA) theories and investigating the underlying therapeutic drugs that may function by reversing the expression of lncRNAs, miRNAs, and mRNAs.

METHODS

RNA (GSE106724, GSE114419, GSE137684, and GSE138518) or miRNA (GSE84376 and GSE138572) expression profile datasets of PCOS patients were downloaded from the Gene Expression Omnibus database. The weighted gene coexpression network analysis (WGCNA) using four RNA datasets was conducted to construct the lncRNA-mRNA coexpression networks, while the common differentially expressed miRNAs in two miRNA datasets and module RNAs were used to establish the ceRNA network. A protein-protein interaction (PPI) network was created to explore the potential interactions between genes. Gene Ontology and KEGG pathway enrichment analyses were performed to explore the functions of genes in networks. Connectivity Map (CMap) and Comparative Toxicogenomics Database (CTD) analyses were performed to identify potential therapeutic agents for PCOS.

RESULTS

Three modules (black, magenta, and yellow) were identified to be PCOS-related after WGCNA analysis, in which KLF3-AS1-PLCG2, MAPKAPK5-AS1-MAP3K14, and WWC2-AS2-TXNIP were important coexpression relationship pairs. WWC2-AS2-hsa-miR-382-PLCG2 was a crucial ceRNA loop in the ceRNA network. The PPI network showed that MAP3K14 and TXNIP could interact with hub genes PLK1 (degree = 21) and TLR1 (degree = 18), respectively. These genes were enriched into mitosis (PLK1), immune response (PLCG2 and TLR1), and cell cycle (TXNIP and PLK1) biological processes. Ten small molecule drugs (especially quercetin) were considered to be therapeutical for PCOS.

CONCLUSION

Our study may provide a novel insight into the mechanisms and therapy for PCOS.

Melatonin may prevent or reverse polycystic ovary syndrome in rats

OBJECTIVE

To evaluate the ovarian effects of melatonin (Mel) in a rat model of polycystic-ovary-syndrome (PCOS) before and after permanent estrus induction.

METHODS

Thirty-two adult-female rats with regular estrous cycle were equally divided into four groups: 1) GCtrl - at estrous phase. 2) GPCOS - at permanent-estrous phase. 3) GMel1 - treated for 60 days with Mel (0.4 mg/Kg) during permanent estrus induction and 4) GMel2 - rats with PCOS and treated for 60 days with Mel. After that, the animals were euthanized, and the ovaries were removed and processed for paraffin embedding. Sections were stained with H.E. for histomorphometry or subjected to immunohistochemistry for Ki-67 and cleaved caspase-3 (Casp-3) detections.

RESULTS

The GPCOS showed lack of corpus luteum and several ovarian cysts, as well as interstitial-like cells. The presence of corpus luteum and a significant increase in primary and antral follicles were observed in Mel-treated groups, which also showed a decrease in the number of ovarian cysts and in the area occupied by interstitial-like cells. These results were more evident in GMel1. The percentage of Ki-67-positive cells was significantly higher in the Mel-treated groups, mainly in the GMel2, as compared to GPCOS. On the other hand, the percentage of Casp-3-positive cells was significantly lower in granulosa cells of GMel1, whereas it was significantly higher in the interstitial-like cells of GMel2, in comparison to GPCOS.

CONCLUSION

Melatonin administration prevents the permanent estrus state in the PCOS rat model. This effect is more efficient when melatonin is administered before permanent estrus induction.

VCAM1 Is Induced in Ovarian Theca and Stromal Cells in a Mouse Model of Androgen Excess

Ovarian theca androgen production is regulated by the pituitary LH and intrafollicular factors. Enhanced androgen biosynthesis by theca cells contributes to polycystic ovary syndrome (PCOS) in women, but the ovarian consequences of elevated androgens are not completely understood. Our study documents the molecular events that are altered in the theca and stromal cells of mice exposed to high androgen levels, using the nonaromatizable androgen DHT. Changes in ovarian morphology and function were observed not only in follicles, but also in the stromal compartment. Genome-wide microarray analyses revealed marked changes in the ovarian transcriptome of DHT-treated females within 1 week. Particularly striking was the increased expression of vascular cell adhesion molecule 1 (Vcam1) specifically in the NR2F2/COUPTF-II lineage theca cells, not granulosa cells, of growing follicles and throughout the stroma of the androgen-treated mice. This response was mediated by androgen receptors (ARs) present in theca and stromal cells. Human theca-derived cultures expressed both ARs and NR2F2 that were nuclear. VCAM1 mRNA and protein were higher in PCOS-derived theca cells compared with control theca and reduced markedly by the AR antagonist flutamide. In the DHT-treated mice, VCAM1 was transiently induced by equine chorionic gonadotropin, when androgen and estrogen biosynthesis peak in preovulatory follicles, and was potently suppressed by a superovulatory dose of human chorionic gonadotropin. High levels of VCAM1 in the theca and interstitial cells of DHT-treated mice and in adult Leydig cells indicate that there may be novel functions for VCAM1 in reproductive tissues, including the gonads.

Tanshinone IIA attenuates estradiol-induced polycystic ovarian syndrome in mice by ameliorating FSHR expression in the ovary

Tanshinone IIA (TSIIA) is a major component of Salvia miltiorrhiza, a Chinese herb that exhibits a therapeutic effect on polycystic ovary syndrome (PCOS). The present study replicated PCOS via the neonatal treatment of estradiol in mice. Estrous cycles, body and ovarian weight, serum levels of testosterone and estradiol were determined. Histological examination of ovaries was performed. The mRNA and protein levels of aromatase luteinizing hormone receptor and follicle-stimulating hormone (FSHR) in ovaries and granule cells were assayed by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. TSIIA was revealed to reverse all disorders induced by estradiol treatment, including prolonged estrous cycles, increased body and ovarian weight, increased atretic cyst-like follicles and decreased corpus luteum, large antral follicles and preovulatory follicles. These improvements in PCOS as a result of TSIIA treatment are likely due to the revised testosterone/estradiol balance, as TSIIA reversed the decrease in aromatase mRNA, the enzyme that converts androgen to estrogen. As the expression of aromatase is regulated by the FSH pathway, TSIIA-mediated elevation in FSHR expression may lead to the upregulation of aromatase. Therefore, TSIIA revises the balance of androgen and estrogen by rescuing the reduced expression of FSHR and aromatase, thus attenuating murine PCOS. The current study aimed to further the application of natural drugs in the treatment of PCOS to confront the side effects of hormone drugs and expand the use of TSIIA.

Is the effect of melatonin on vascular endothelial growth factor receptor-2 associated with angiogenesis in the rat ovary?

OBJECTIVES

Vascular endothelial growth factor (VEGF) and its receptors play important roles in angiogenesis. Melatonin plays an important role in gonadal development; thus, its effect on the reproductive system is evident. We investigated the influence of melatonin on the expression of VEGF, vascular endothelial growth factor receptor-1 (VEGFR1) and vascular endothelial growth factor receptor-2 (VEGFR2), as well as on changes in oxidative stress markers and follicle numbers in rat ovaries.

METHODS

For this purpose, 45 Wistar rats were separated into the following groups: Group 1, control; Group 2, vehicle; and Group 3, melatonin. Rats in Group 3 were treated with melatonin at 50 mg/kg/day for 30 days. The effects of melatonin on the expression of VEGF, VEGFR1 and VEGFR2 were established by immunohistochemistry analysis. The effects of melatonin on antioxidant enzyme activities were demonstrated by spectrophotometric analysis.

RESULTS

Based on immunohistochemistry analysis, VEGFR2 was predominantly localized to theca cells in the ovary. Our data indicate that melatonin treatment can significantly increase VEGF and VEGFR1 expression in the ovary ( p <0.05). Additionally, the number of degenerated follicles significantly decreased with melatonin treatment ( p <0.05). Melatonin administration also led to significant increases in antioxidant enzyme levels in the ovary.

CONCLUSION

Melatonin treatment exerts protective effects on follicles against increased lipid peroxidation through modulating tissue antioxidant enzyme levels. These effects may be related to angiogenesis and antioxidant activities.

miR-323-3p regulates the steroidogenesis and cell apoptosis in polycystic ovary syndrome (PCOS) by targeting IGF-1

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic heterogeneous disorder. The incidence of which reaches 5% to 10% among reproductive-age women. Abnormal folliculogenesis is considered to be a common characteristic of PCOS, but the cause of this disorder and its pathogenesis still remain uncertain. Previous studies had proved that dysregulation of microRNAs is related to the pathogenesis of PCOS. In this study, we investigated the effect of miR-323-3p on the human cumulus cells (CCs). We also investigated the underlying mechanisms of miR-323-3p on human granulosa-like tumor cell line (KGN) or primary human CCs by stimulating with Dihydrotestosterone (DHT). Our findings suggested that the level of miR-323-3p in human CCs of women with PCOS was down-regulated, compared with that of the control group. Moreover, the inhibition of the level of miR-323-3p could up-regulate of the steroidogenesis and promote the apoptosis in KGN cells. In addition, our data confirmed that the Insulin-like growth factor 1 (IGF-1) gene was the direct target of miR-323-3p. Furthermore, the mimic of miR-323-3p inhibited the expression of IGF-1, which down-regulated the levels of AR, AMHR-II, CYP19A, EGFR, and GATA-4. In conclusion, miR-323-3p targeting IGF-1 regulates the steroidogenesis and the activity of CCs, which plays an important role in the occurrence and development of PCOS. Our results have shown that miR-323-3p is a novel and promising molecular target for the improvement of the dysfunction of CCs in PCOS.

How to choose the suitable animal model of polycystic ovary syndrome?

Polycystic ovary syndrome (PCOS) is a gynecological metabolic and endocrine disorder with uncertain etiology. To understand the etiology of PCOS or the evaluation of various therapeutic agents, different animal models have been introduced. Considering this fact that is difficult to develop an animal model that mimics all aspects of this syndrome, but, similarity of biological, anatomical, and/or biochemical features of animal model to the human PCOS phenotypes can increase its application. This review paper evaluates the recently researched animal models and introduced the best models for different research purposes in PCOS studies. During January 2013 to January 2017, 162 studies were identified which applied various kinds of animal models of PCOS including rodent, primate, ruminant and fish. Between these models, prenatal and pre-pubertal androgen rat models and then prenatal androgen mouse model have been studied in detail than others. The comparison of main features of these models with women PCOS demonstrates higher similarity of these three models to human conditions. Thereafter, letrozole models can be recommended for the investigation of various aspects of PCOS. Interestingly, similarity of PCOS features of post-pubertal insulin and human chorionic gonadotropin rat models with women PCOS were considerable which can make it as a good choice for future investigations.

Vitamin D3 regulates steroidogenesis in granulosa cells through AMP-activated protein kinase (AMPK) activation in a mouse model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic disorder in reproductive-aged women. Hormonal abnormality caused by steroidogenesis disturbances appears to be the main culprit of the clinical picture in PCOS. Vitamin D3 could regulate steroidogenesis in granulosa cells, but the mechanism of action of vitamin D3 on steroidogenesis remains unknown. AMP-activated protein kinase (AMPK) has a modulating role in steroid hormone production. We investigated the effect of vitamin D3 on steroidogenesis in cultured granulosa cells of dehydroepiandrosterone-induced PCOS mice and studied the involvement of AMPK signalling pathway in the current process. Immunoblotting assay showed that vitamin D3 could increase phosphorylation of AMPK alpha and acetyl-CoA carboxylase, main substrate of AMPK. Vitamin D3 and 5-aminoimidazole-4-carboxamide-1-β-D-riboside or Aicar (AMPK activator) not only reduced gene expression of steroidogenic enzymes (P450scc or Cyp11a1, StAR, Cyp19a1 and 3B-HSD), but also reduced production of progesterone and 17B-estradiol assessed by radioimmunoassay. Pretreatment with compound C (AMPK inhibitor) decreased APMK phosphorylation and eliminated the effects of vitamin D3 and Aicar on steroidogenic enzymes expression and estradiol and progesterone production. This study showed that vitamin D3 has the main role in regulating of steroidogenesis in granulosa cells of mouse polycystic ovary through activation of the AMPK signalling pathway.

SIGNIFICANCE OF THE STUDY

Polycystic ovarian syndrome (PCOS) is an endocrine disorder of women in reproductive age. This disorder is partly related to disruption in steroidogenesis pathway and dysregulation of estradiol and progesterone production in granulosa cells of polycystic ovaries. Previously, we have shown that vitamin D3 could modulate steroidogenesis pathway in PCOS granulosa cells. In this study, we investigate the molecular mechanism of vitamin D3 in regulation of steroidogenesis pathway. We have shown that vitamin D3 has a modulating role in steroidogenesis pathway of granulosa cells by regulation of AMP-activated protein kinase (AMPK) as an underlying molecular mechanism in mouse polycystic ovary.

Combined effects of ovariectomy and streptozotocin-induced diabetes in the articular cartilage of rats

AIM

To evaluate the combined effects of streptozotocin-induced diabetes (Di) and ovariectomy in the articular cartilage of rats.

METHODS

Forty adult female Wistar rats were ovariectomized (OVX) or sham-operated. After recovery from surgery, the animals were assigned randomly into four groups: OVX control (OVX-C); OVX treated with 10 µg/kg/day of 17β-estradiol (OVX-E); sham-operated subjected to Di (Sham-Di); and OVX subjected to Di (OVX-Di). After 60 days of treatment, the animals were euthanized and the distal femurs with articular cartilage were processed for paraffin-embedding. Sections were stained with hematoxylin and eosin for histomorphometry, Picro-Sirius Red for collagen, or Alcian Blue for glycosaminoglycan (GAG) content. To detect apoptosis, sections were stained with an antibody to cleaved caspase-3 (casp-3).

RESULTS

Articular cartilage thickness and GAG content were significantly lower (p < 0.05) in the OVX-Di group, which also showed a higher number of casp-3-positive chondrocytes than the other groups. Interestingly, the higher percentage (p < 0.05) of mature collagen fibers was seen in the OVX-Di group, may be as a result of a reduced extracellular matrix remodeling of the articular cartilage.

CONCLUSION

Our results indicate that the combination of ovariectomy and streptozotocin-induced diabetes produces more deleterious effects in articular cartilage of rats than either condition alone.

Biochemical, Histopathological and Immunohistochemical Evaluation of the Protective and Therapeutic Effects of Thymoquinone against Ischemia and Ischemia/Reperfusion Injury in the Rat Ovary

AIM

To evaluate the antioxidant effects of thymoquinone (TQ) and to investigate the biochemical, histopathological and immunohistochemical changes in experimental rat ovarian torsion.

METHODS

A total of 48 female adult rats were used in this study and randomly divided into 7 groups: (1) sham operation; (2) bilateral 3-hour ovarian ischemia; (3) 3-hour ischemia and 3-hour reperfusion; (4) and (5) rats were administered 20 and 40 mg/kg of TQ, respectively, before 0.5 h of ischemia, and then 3 h of ovarian ischemia was applied; (6) and (7) 3-hour ovarian ischemia was applied; 2.5 h after the induction of ischemia, rats were administered the same doses of TQ; at the end of 3 h of ischemia, a 3-hour reperfusion was applied. Histologic changes under light microscopy, immunoreactivity for anticaspase-3 and serum levels of malondialdehyde, interleukin-6, catalase and glutathione peroxidase were noted and compared between the 7 groups.

RESULTS

Ischemia and ischemia/reperfusion cause a deterioration of biochemical and histopathological parameters. Administration of TQ seems to reverse these alterations and alleviate the injury. Antioxidant defense mechanisms appear to be enhanced by the administration of TQ.

CONCLUSION

TQ at different doses attenuates ovarian ischemia and ischemia/reperfusion injury in rats.

Epigenetic pattern changes in prenatal female Sprague-Dawley rats following exposure to androgen

Androgen excess is generally considered to be one of the major characteristics of polycystic ovary syndrome (PCOS). Evidence from both clinical research and animal studies has revealed that this syndrome may have fetal origins, with epigenetics being proposed as the underlying mechanism. Our PCOS rat model induced by prenatal administration of 3mg testosterone from Embryonic Day (E) 16 to E19 showed polycystic ovaries, irregular oestrous cycles and endocrine disorders in adulthood. The methylation status of 16, 8 and 4 cytosine-phosphate-guanine (CpG) sites in the promoter regions of the androgen receptor (Ar), cytochrome P450 family 11, subfamily A, polypeptide 1 (Cyp11a1) and cytochrome P450, family 17, subfamily A, polypeptide 1 (Cyp17a1) genes, respectively, were measured by pyrosequencing. We identified three hypomethylated sites (CpG +58, +65 and +150) in Ar and one hypomethylated site (CpG +1016) in Cyp11a1 in peripheral blood cells of prenatally androgenised (PNA) rats. In ovarian tissue, five CpG sites of Ar (CpG +87, +91, +93, +98, +150) and one single CpG site in Cyp11a1 (CpG +953) were significantly hypomethylated in PNA rats, but the modified methylation of these two genes may not be sufficient to significantly alter levels of gene expression. Furthermore, tissue-specific methylation analysis revealed that both Ar and Cyp11a1 exhibited significant hypomethylation in testis in contrast with ovary and blood. PNA may lead to methylation pattern changes and the development of PCOS, but further studies are required to reveal causal relationships.

Effects of metformin on the adrenal cortex of androgenized rats

OBJECTIVE

To evaluate the sex steroid profile and histomorphometry of the adrenal cortical zones of androgenized rats (wistar) with polycystic ovary syndrome treated with metformin.

STUDY DESIGN

Thirty animals were divided into three groups: GC (regular estrous cycle), GPE (permanent estrus), and GPEM (permanent estrus + metformin 28 mg/kg for 50 days). At the end of this period, blood was collected for hormone measurement. The width of the adrenal cortical zones and the nuclear volumes were analyzed by histomorphometry. The ANOVA test was used in the statistical analysis.

RESULTS

The adrenal glands of the androgenized animals were larger and more intensely vascularized than those of the other groups. The concentration of androstenedione in GPE was higher than that in the other groups (0.4 ± 0.1*>= 0.2 ± 0.1 = 0.2 ± 01, *p < 0.05). The width of the zona glomerulosa and of the zona reticularis and their nuclear volumes were greater in GPE compared to those of the other groups (GPE* > GPEM = GC, *p < 0.05).

CONCLUSION

Metformin treatment may decrease the serum levels of androstenedione as well as the width and the nuclear volumes of the zona glomerulosa and of the zona reticularis in androgenized animals.