Role of oxidative stress and low-grade inflammation in letrozole-induced polycystic ovary syndrome in the rat

Synergistic Amelioration of Letrozole-induced Polycystic Ovary Syndrome in Rats: A Therapeutic Approach with Apple Cider Vinegar and Metformin Combination

The present study was conducted to evaluate the combination effect of apple cider vinegar (ACV) and metformin against letrozole-induced polycystic ovary syndrome (PCOS). Female Wistar rats were administered letrozole (1 mg/kg/day, p.o) for 21 days, except for the control group of animals. On the 22nd day, PCOS-induced animals were segregated into 4 groups and administered with CMC, ACV, metformin, and a combination of ACV and metformin, respectively. The treatments were continued for 15 days, and on the 36th day, all the animals were sacrificed for biochemical (blood glucose, lipid profile), hormonal (sex hormones and adiponectin), and pro-inflammatory mediator estimations in blood samples. The ovarian tissue samples were used for oxidative stress parameters and histological alterations. The PCOS control animals showed a significant alteration in the estrous cycle. The administration of letrozole resulted in the alteration of hormonal balance and elevation of body weights, glycemic state, lipid profile, pro-inflammatory mediators in serum, and oxidative stress in ovarian samples. Individual treatment groups and combination treatment groups reversed the letrozole-induced alterations in PCOS animals, and more promising results were observed with combination therapy than with individual treatment groups. Further, the therapeutic potential of the combination treatment group was also confirmed by the histological observations in the ovarian samples. The study showed that the combination of ACV and metformin significantly alleviated letrozole-induced PCOS complications in rats. This might have been achieved by mitigating the hormonal imbalance, pro-inflammatory, hyperglycemic, and hyperlipidemic states in serum, and oxidative stress in the ovary samples.

The value of low-intensity pulsed ultrasound in reducing ovarian injury caused by chemotherapy in mice

BACKGROUND

Ovarian damage and follicle loss are major side effects of chemotherapy in young female patients with cancer. However, effective strategies to prevent these injuries are still lacking. The purpose of this study was to verify low-intensity pulsed ultrasound (LIPUS) can reduce ovarian injury caused by chemotherapy and to explore its underlying mechanisms in mice model.

METHODS

The mice were randomly divided into the Control group, Cisplatin group, and Cisplatin + LIPUS group. The Cisplatin group and Cisplatin + LIPUS group were intraperitoneally injected with cisplatin every other day for a total of 10 injections, and the Control group was injected with saline. On the second day of each injection, the Cisplatin + LIPUS group received irradiation, whereas the other two groups received sham irradiation. We used a variety of biotechnologies to detect the differences in follicle count, granulosa cell apoptosis, fibrosis, transcriptome level, oxidative damage, and inflammation in differently treated mice.

RESULT

LIPUS was able to reduce primordial follicle pool depletion induced by cisplatin and inhibit the apoptosis of granulosa cells. Transcriptomic results confirmed that LIPUS can reduce ovarian tissue injury. We demonstrated that LIPUS can relieve ovarian fibrosis by inhibiting TGF-β1/Smads pathway. Meanwhile, it can reduce the oxidative damage and reduced the mRNA levels of proinflammatory cytokines caused by chemotherapy.

CONCLUSION

LIPUS can reduce the toxic effects of chemotherapy drugs on ovaries, inhibit ovarian fibrosis, reduce the inflammatory response, and redcue the oxidative damage, reduce follicle depletion and to maintain the number of follicle pools.

Gut Microbes in Polycystic Ovary Syndrome and Associated Comorbidities; Type 2 Diabetes, Non-Alcoholic Fatty Liver Disease (NAFLD), Cardiovascular Disease (CVD), and the Potential of Microbial Therapeutics

Polycystic ovary syndrome (PCOS) is one of the most common endocrine anomalies among females of reproductive age, highlighted by hyperandrogenism. PCOS is multifactorial as it can be associated with obesity, insulin resistance, low-grade chronic inflammation, and dyslipidemia. PCOS also leads to dysbiosis by lowering microbial diversity and beneficial microbes, such as Faecalibacterium, Roseburia, Akkermenisa, and Bifidobacterium, and by causing a higher load of opportunistic pathogens, such as Escherichia/Shigella, Fusobacterium, Bilophila, and Sutterella. Wherein, butyrate producers and Akkermansia participate in the glucose uptake by inducing glucagon-like peptide-1 (GLP-1) and glucose metabolism, respectively. The abovementioned gut microbes also maintain the gut barrier function and glucose homeostasis by releasing metabolites such as short-chain fatty acids (SCFAs) and Amuc_1100 protein. In addition, PCOS-associated gut is found to be higher in gut-microbial enzyme β-glucuronidase, causing the de-glucuronidation of conjugated androgen, making it susceptible to reabsorption by entero-hepatic circulation, leading to a higher level of androgen in the circulatory system. Overall, in PCOS, such dysbiosis increases the gut permeability and LPS in the systemic circulation, trimethylamine N-oxide (TMAO) in the circulatory system, chronic inflammation in the adipose tissue and liver, and oxidative stress and lipid accumulation in the liver. Thus, in women with PCOS, dysbiosis can promote the progression and severity of type 2 diabetes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular diseases (CVD). To alleviate such PCOS-associated complications, microbial therapeutics (probiotics and fecal microbiome transplantation) can be used without any side effects, unlike in the case of hormonal therapy. Therefore, this study sought to understand the mechanistic significance of gut microbes in PCOS and associated comorbidities, along with the role of microbial therapeutics that can ease the life of PCOS-affected women.

Comparison of Letrozole and Clomiphene Citrate in Pregnancy Outcomes in Patients with Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis

Clomiphene citrate (CC) and letrozole are the predominant medical interventions for the management of infertility in patients with polycystic ovary syndrome (PCOS). To comprehensively summarize the evidence, a systematic review and meta-analysis of randomized clinical trials (RCTs) was carried out to assess the effect of letrozole and CC on pregnancy outcomes in PCOS patients. We searched PubMed/MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials from inception to January 2023. We included RCTs conducted on PCOS women comparing letrozole to CC and assessing endometrial thickness, the number and size of follicles, and ovulation and pregnancy rates. The endpoints were summarized as risk ratio (RR) or standardized mean difference (SMD) with 95% confidence interval (CI) using the random-effects model. Heterogeneity was examined using the I2 statistic. Fifty trials met our inclusion criteria. The mean endometrial thickness was significantly higher in the letrozole group compared to CC group (SMD: 0.89; 95% CI: 0.49, 1.28; I2=97.72%); however, the number of follicles was higher in the CC group (SMD: -0.56; 95% CI: -0.96, -0.17; I2=96.34%). Furthermore, letrozole intake induced higher ovulation rate (RR: 1.20; 95% CI: 1.13, 1.26; I2=54.49%) and pregnancy rate (RR: 1.44; 95% CI: 1.28, 1.62; I2=65.58%) compared to CC. Compared to CC, letrozole has a positive effect on endometrial thickness, monofollicular development, and ovulation and pregnancy rates suggesting that letrozole may be a strong alternative to CC as a first-line medical intervention for chronic anovulation in PCOS women. Larger studies are warranted to further clarify these findings.

Evaluating the potential of daily intake of polystyrene microplastics via drinking water in inducing PCOS and its ovarian fibrosis progression using female zebrafish

Polystyrene microplastics, extensively considered endocrine disrupting chemicals, disturb the reproductive system of living organisms. Polycystic ovary syndrome (PCOS), the reproductive endocrinopathy, is longstanding concern due to its eternal impacts as reproductive disorder and infertility. Despite several reports in reproductive and endocrine toxicity, there is inadequate literature regarding the daily intake of polystyrene-microplastics via drinking water in causing PCOS and leading to ovarian fibrosis in long-term. The present study investigated whether daily consumption of polystyrene-microplastics at doses equivalent to human exposure can cause PCOS and progress to ovarian fibrosis, using female zebrafish as model. Resembling letrozole-PCOS zebrafish model, daily intake of polystyrene-microplastics displayed hallmark PCOS pathophysiology; like excess body weight and %Gonadosomatic index, decreased Follicle Stimulating Hormone and β-estradiol, increased Luteinising Hormone, brain and ovarian Testosterone (39.3% and 75% respectively). Correspondingly, ovarian histology revealed more developing (stage I and II) oocytes and less mature oocytes alongwith cystic lesions; like follicular membrane disorganization, zona pellucida invagination, theca hypertrophy, basophilic granular accumulation and oocyte buddings. Lipid deposition in intestinal and ovarian tissues was evidenced and increased fasting blood glucose manifesting insulin resistance. The expression of PCOS biomarkers (tox3, dennd1a, fem1a) was significantly disturbed. Polystyrene microplastics played vital role in inducing PCOS further enhancing oxidative stress, which positively influences inflammation and aggravate ovarian mitophagy, shedding light on its ability to harshen PCOS into ovarian fibrosis, which is characterized by collagen deposition and upregulation of pro-fibrogenic biomarker genes. These findings illustrate the potential of daily microplastics intake via drinking water in triggering PCOS and its progression to ovarian fibrosis.

Effects of Letrozole Treatment and Vitamin C Supplementation on Morphology, Endoplasmic Reticulum Stress, Programmed Cell Death, and Oxidative Stress in the Small Intestine of Adult Male Rats

Estrogens are hormones that play an important role in the digestive tract, including in men. Letrozole is an inhibitor of cytochrome P450 aromatase, an enzyme converting androgens to estrogens. The use of letrozole may cause oxidative stress and endoplasmic reticulum stress in the cells. Factors modulating cellular stress may include vitamin C. The purpose of this study was to examine whether letrozole and/or vitamin C supplementation can affect the morphology of the small intestine, the parameters of endoplasmic reticulum stress, programmed cell death markers, and oxidative damage. Three-month-old male rats were divided into four groups and treated with the following: (I) CTRL-water; (II) CTRL+C-L-ascorbic acid; (III) LET-letrozole; and (IV) LET+C-letrozole + L-ascorbic acid. The morphometrical measurements included epithelial thickness, crypt and lumen area, crypt perimeter, nuclei number in the crypt, and the cell size of crypts. The expression levels of PERK, caspase-3, and catalase were determined. Significant differences in the morphometrical measurements and immunoexpression were observed. This may indicate that chronic treatment with letrozole can affect morphology and induce ER stress, oxidative stress, and programmed cell death in the epithelial cells of the small intestine of adult male rats. Vitamin C supplementation exerts an effect on some parameters of the molecular processes.

Blood volatile organic compounds as potential biomarkers for poly cystic ovarian syndrome (PCOS): An animal study in the PCOS rat model

Polycystic ovary syndrome (PCOS) as a common metabolic and endocrinological disorder can affect the metabolic profile in biological fluids. We studied the profile of blood volatile organic compounds (VOCs) in rats with PCOS and controls to identify potential specific biomarkers of blood VOCs in PCOS rats. For this purpose, 30 female adult Wistar rats were assigned to two groups: control and PCOS groups. PCOS model was induced using letrozole gavage (1 mg/kg) for 21 days. The rats in the control group received water of the same volume for 21 days. During treatment, a collection of vaginal smears was done every day for estrus cycle determination and weight was measured weekly. On the day after the last administration of letrozole, the rats were killed and their blood and ovaries were collected. Testosterone levels and histologic changes in ovaries were examined. Also, headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) analyzed the VOCs in the blood of PCOS and control rats. Multivariate and univariate statistical analyses were used to find the potential biomarkers for a rat model of PCOS. Weight gain, ovarian and vaginal pathological alteration, as well as hyperandrogenemia, confirmed the successful induction of the PCOS in rats. The results of blood VOCs analysis showed that nine VOCs were significantly elevated and one VOC decreased in the PCOS group than the control group (P < 0/05). The partial least-squares discriminant analysis (PLS-DA) and principal component analysis (PCA) showed good separation of VOCs between the PCOS rats and the control group. The 4-ethylphenol and capric (decanoic) acid were selected as the potential biomarkers for PCOS diagnosis in the blood of the PCOS rats. The blood of PCOS rats had a specific profile of VOCs, which could be detected by GC-MS analysis. These findings can pave the way for further studies towards developing a new screening method for PCOS detection and studying their pathology, based on VOCs analysis.

Ketogenic diet restores hormonal, apoptotic/proliferative balance and enhances the effect of metformin on a letrozole-induced polycystic ovary model in rats

OBJECTIVE

Polycystic ovaries (PCO) is a hormonal disorder that is a leading cause of infertility. The formation of multiple persistent cysts and hormonal imbalance are hallmarks of PCO. Recent clinical studies reported a beneficial effect of the ketogenic diet (KD; high-fat, low-carbohydrate) on PCO. The aim of this study was to investigate the effect of the KD alone and in combination with metformin on letrozole-induced PCO in female rats.

METHODS

Female rats were grouped into control and PCO (letrozole; 1 mg/kg for 21 days). The PCO group was subdivided into PCO (non-treated), PCO-metformin (300 mg/kg), PCO rats fed with KD only, and PCO rats treated with metformin and fed with KD. All groups continued to receive letrozole during the 21-day treatment period. At the end of the experiment, serum and ovaries were collected for further analysis.

RESULTS

The untreated-PCO rats showed increased testosterone, LH/FSH ratio, and ovary weights. Disturbed apoptosis and proliferation balance were evident as a low caspase-3 activation and proliferating cell nuclear antigen expression and increased TGF-β expression. The KD improved the letrozole-induced effects, which was comparable to the effect of metformin. Combining the KD with metformin treatment additively enhanced the metformin effect.

CONCLUSION

Our results indicate that the KD has a protective role against PCO in rats, especially when combined with metformin. This study reveals a potential therapeutic role of the KD in PCO, which could prompt valuable future clinical applications.

Dysregulation of intraovarian redox status and steroidogenesis pathway in letrozole-induced PCOS rat model: a possible modulatory role of l-Carnitine

Background

Polycystic ovarian syndrome (PCOS) is a reproductive disorder associated with several endocrine and metabolic alterations. The mechanism underlying this syndrome is controversial. On the other hand, drugs used for the treatment are associated with several side effects and poor in controlling PCOS phenotype. l-Carnitine (LC) has been reported to have a significant regulatory function on the redox and metabolic status of female reproductive system. Nevertheless, its regulatory pathways to regulate PCOS are still under investigation. Therefore, this study aimed to evaluate the effects of LC on the steroidogenic pathways, oxidative stress markers and metabolic profile in letrozole (LTZ)-induced PCOS rat model.

Methods

For this aim, animals were divided into four groups (n = 6). Control group, untreated letrozole-induced PCOS group (1 mg/kg bwt) for 21 days, PCOS group treated with l-Carnitine (100 mg/kg bwt) for 14 days and PCOS group treated with clomiphene citrate (2 mg/kg bwt) for 14 days. Finally, body and ovarian weight, metabolic state(glucose and lipid profile), hormonal assays (testosterone, 17 β estradiol, LH and FSH levels), intraovarian relative gene expression (CYP17A1, StAR, CYP11A1 and CYP19A1 genes), ovarian redox state (malondialdehyde (MDA), reduced glutathione content (GSH) and catalase enzyme activity (CAT)) as well as serum total antioxidant capacity (TAC) were detected. Also, histomorphometric ovarian evaluation (number and diameter of cystic follicles, granulosa cell thickness and theca cell thickness) as well as immune expression of caspase-3 of granulosa cells of cystic follicles were determined.

Results

LC significantly improved ovarian redox state (GSH, MDA and CAT), steroidogenic pathways gene expression (CYP17A1, StAR, CYP11A1 and CYP19A1 genes), hormonal profile (Follicle stimulating hormone (FSH) and luteinizing hormone (LH), testosterone and estradiol), metabolic state (Glucose and lipid profile) histomorphometric alterations and decreased caspase 3 immune reaction of granulosa cells.

Conclusion

l-Carnitine supplementation can ameliorate the PCOS phenotype through its energetic, antioxidant and antiapoptotic functions as well as steroidogenesis regulatory role. This protocol could be modified to produce the best therapeutic benefits, and it could be regarded as a prospective therapeutic intervention for PCOS.

Rhamnocitrin Attenuates Ovarian Fibrosis in Rats with Letrozole-Induced Experimental Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine-related cause of infertility in women and has an unknown etiology. Studies have shown that rhamnocitrin (Rha) exhibits positive effects on the reproductive system. This study investigated Rha's antifibrotic effects on PCOS rats and revealed its underlying mechanisms. Female SD rats were randomized into 4 groups (n = 8, each); the control group received tea oil by intraperitoneal injection and 1% w/v CMC by oral gavage; the PCOS group received letrozole (1 mg/kg); the PCOS+Rha group received letrozole and Rha (5 mg/kg); the PCOS+Met group received letrozole and Met (265 mg/kg) for 21 days. At the study end, Rha treatment restored letrozole-induced alterations in the relative ovarian weights, body weight, and relative weights of uterine and visceral adipose tissues. Histological observation showed that Rha ameliorates ovarian structure and fibrosis in PCOS. Administration of Rha reduced letrozole-induced metabolic dysfunction by ameliorating the levels of TC, TG, and HDL-C in the PCOS rats. Rha treatment also modulated the serum levels of sex hormones, which decreased T, E2, and LH and increased FSH in PCOS rats. In addition, Rha treatment modulated insulin resistance and increased gene expression of antioxidant enzymes (Cat, Sod2, Gpx3, Mgst1, Prdx3, Gsta4, Gsr, and Sod1) in the ovaries of the PCOS rats. Finally, Rha treatment appeared to increase the activity of PPAR-γ and inhibit the TGF-β1/Smad pathway in the ovaries of the PCOS rats. Our findings suggest that Rha significantly ameliorated metabolic disturbances and ovarian fibrosis in the PCOS rats. Rha perhaps is an effective compound for preventing ovarian fibrosis in the future.

Diacerein ameliorates induced polycystic ovary in female rats via modulation of inflammasome/caspase1/IL1β and Bax/Bcl2 pathways

Polycystic ovary syndrome (PCOS) is a very common gynecological disease during childbearing period and markedly affects female fertility. Until now, there are no studies evaluating the possible curative effect of diacerein (DIA) in induced PCOS. For the first time, we aimed in current model to study the effect of DIA (50 mg/kg/day) orally for 3 weeks on experimentally induced PCOS by letrozole (1 mg/kg/day) for 3 weeks. We measured rats' body weight changes, levels of serum insulin, anti-Müllerian hormone (AMH), testosterone, inflammasome, caspase1, and total anti-oxidant capacity (TAC). Moreover, we measured ovarian tissue parameters as malondialdehyde (MDA), interleukin 1β (IL1β), real-time polymerase chain reaction (rt-PCR) of Bcl2-associated X protein (Bax), and interleukin 10 (IL10) gene expression changes. Furthermore, histopathological features and anti-apoptotic marker B cell lymphoma 2 (Bcl2) immunoexpression changes were evaluated. Our results showed that letrozole markedly induced PCOS as manifested by significant increase in serum testosterone, insulin, AMH, rats' body weights, ovarian tissue MDA, IL1β, inflammasome, and caspase1 but decrease of serum TAC. In addition, gene expression of Bax increased but IL10 gene expression decreased. Ovaries showed the typical histopathological changes of PCOS with no immunoexpression of Bcl2. DIA was greatly able to ameliorate letrozole-induced PCOS changes in rats mainly via prevention of IL1β, and improving metabolic disturbances, and its anti-apoptotic, anti-oxidant, and anti-inflammatory effects with further regulation of inflammasome/caspase1/IL1β and Bax/Bcl2 pathways.

Role of 14-3-3β protein on ovarian folliculogenesis, steroidogenesis and its correlation in the pathogenesis of PCOS in mice

This study was designed to assess for the first time the circulating and ovarian level of 14-3-3β protein in the PCOS mice and the possible correlation between 14-3-3β protein with PCOS related increase in testosterone (HA), insulin levels (HI) and reduced insulin sensitivity in the ovary. PCOS was induced in mice using treatment of letrozole (by oral gavage) for 21 days. Immunohistochemical study showed increased expression of 14-3-3β protein in PCOS ovary compared to the control ovary. The circulating testosterone and insulin levels, together with circulating and ovarian levels of 14-3-3β protein also showed significant increase in PCOS mice compared to the control mice. An increase in 14-3-3β protein was observed positively correlated with circulating testosterone and insulin levels but showed a negative correlation with ovarian expression of insulin receptor protein in PCOS mice. The treatment of 14-3-3β protein in vitro to the normal ovary showed a significant increase in testosterone synthesis but a significant decline in insulin receptor protein expression compared to the vehicle-treated ovary of adult mice. The present study showed the direct role of 14-3-3β protein in increasing testosterone synthesis along with decreasing insulin sensitivity. Thus, 14-3-3β protein may be playing possible role in PCOS pathogenesis.

Effects of mulberry leaf silage on antioxidant and immunomodulatory activity and rumen bacterial community of lambs

Background

Rumen is a natural fermentation system and the microorganisms inside can effectively utilize plant bioresource and interact with host metabolism. Here, analysis of rumen microbiome, together with animal performance and serum metabolism in a lamb model were performed to identify the potential use of mulberry leaf silage (MS) to replace alfalfa silage (AS) as a new functional feed resource and to mining the novel specific mulberry leaf associated rumen bacteria interact with host metabolism.

Results

The lambs fed with MS diet showed improved antioxidant capacity and immune function compared to those fed AS diet. The MS diet significantly altered rumen microbiota α- and β-diversity and taxonomic composition. Microbial analysis revealed that Bifidobacterium, Lactobacillus and Schwartzia were enhanced, and Ruminococcaceae UCG-010 and Lachnospiraceae_XPB1014_group were down-regulated in the rumen of MS group. A strong association was also found between these rumen microbial taxa and host antioxidant and immunomodulatory capacity.

Conclusion

These findings indicated that mulberry leaf silage can be a high-quality feed source or bioactive pharmaceutical that is responsible for ruminant’s health benefits. The modified rumen microbial community by mulberry leaf silage were associated with the enhanced antioxidant capacity and immunomodulatory of lambs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-021-02311-1.

Cardiovascular Properties of the Androgen-Induced PCOS Model in Rats: The Role of Oxidative Stress

Polycystic ovary syndrome (PCOS) is a multifaced reproductive endocrinopathy affecting 6-20% of women of childbearing age. It was previously shown that women with PCOS have an increased risk of cardiovascular (CV) diseases. The aim of this study was to evaluate the cardiodynamic parameters of isolated rats' hearts, blood pressure levels, and histomorphological changes in the heart tissue following the androgen-induced PCOS model in rats and the role of oxidative stress in the development of these CV properties of PCOS. 21-day-old female rats (n = 12) were divided into control and PCOS groups. PCOS was induced by administration of testosterone enanthate (1 mg/kg BW, daily) during 35 days. During the autoregulation protocol (40-120 mmHg) on the Langendorff apparatus, ex vivo cardiodynamic parameters of retrogradely perfused hearts showed enhanced contractile function and increased lusitropic effects in the left ventricle (LV) in PCOS rats. Systolic and diastolic pressures in LV were elevated at all perfusion pressure values. Systemic arterial systolic blood pressure showed borderline elevation, while mean arterial blood pressure was significantly higher in PCOS rats. Histological evaluation of heart tissue depicted hypertrophic (8.3%) alterations in LV cardiomyocytes and increase (7.3%) in LV wall thickness. Oxidative stress parameters were altered in systemic circulation, coronary venous effluent (CVE), and heart tissue. Levels of superoxide dismutase and reduced glutathione were decreased in blood and heart tissue, while catalase activity was not altered. Degree of lipid peroxidation was increased in circulation as well as heart tissue. Increased levels of O₂⁻ in CVE indicated the cardiotoxic effects in the rat PCOS model. The mentioned alterations of oxidative stress parameters in the blood, CVE, and heart could be recommended as potential contributors underlying the development of CV risk in PCOS women.

Pharmaceutical and Pharmacological Evaluation of the Effect of Nano-Formulated Spironolactone and Progesterone on Inflammation and Hormonal Levels for Managing Hirsutism Experimentally Induced in Rats

Hirsutism is a dermatological condition that refers to the excessive growth of hair in androgen-sensitive areas in women. Recently, the enhancement of the visible signs of a hairy female has taken special concern that affected the quality of life. The present study was developed to compare the follicular targeting effect of topical spironolactone (SP) or progesterone (PG)-loaded nanostructured lipid carrier (NLC) on the management of hirsutism. Four NLC formulations were prepared using cold homogenization techniques and pharmaceutically evaluated. SP-NLC and PG-NLC topical hydrogels were prepared to explore their pharmacological effect on letrozole induced polycystic ovarian syndrome (PCOS) in rats. Inflammatory mediators, antioxidant, and hormonal parameters were assayed. Additionally, histopathological examination was carried out to confirm the successful induction of PCOS. Results confirmed that all NLC formulations have a spherical shape with particle size ranged from 225.92 ± 0.41 to 447.80 ± 0.66 nm, entrapment efficiency > 75%, and zeta potential (- 31.4 to - 36.5 mV). F1 and F3 NLCs were considered as selected formulations for SP and PG, respectively. Female Wistar rats treated with F1 formulation for 3 weeks displayed better outcomes as manifested by the measured parameters as compared to the other tested groups. A significant reduction in hair follicle diameter and density was observed after topical application of SP or PG nano-gels. Finally, the outcomes pose a strong argument that the development of topically administered SP-NLC can be explored as a promising carrier over PG-NLC for more effectual improvement in the visible sign of hirsutism.

Uterine anomalies in cell proliferation, energy homeostasis and oxidative stress in PCOS hamsters, M. auratus: Therapeutic potentials of melatonin

AIMS

Polycystic ovarian syndrome (PCOS) is a reproductive, endocrine and metabolic disorder. Less is known about the mechanism of its effect on uterine function and therapeutic potential of melatonin. Our aim was to evaluate uterine dysfunction(s) in letrozole induced PCOS and its possible rectification by melatonin.

MAIN METHODS

Adult female golden hamsters were divided into groups of Control (C), Melatonin (M; 1 mg/kg b.w.), Letrozole (L; 3 mg/kg b.w.) and combination of Letrozole+Melatonin (L + M; 3 mg/kg b.w. + 1 mg/kg b.w.) which were treated for 40 days. Analysis of serum testosterone/estradiol/progesterone/leptin/insulin, uterine histomorphometry, immunohistochemistry for proliferation cell nuclear antigen (PCNA), homeostatic assessment model of insulin resistance (HOMA-IR), western blotting for PCNA, androgen receptor (AR), insulin receptor (InsR), glucose tansporter-4 (GLUT-4), nuclear factor-kappa B (NFκB), cyclooxygenase-2 (COX-2) and biochemical analysis of superoxide dismutase (SOD)/catalase/lipid peroxidation (LPO) were done.

KEY FINDINGS

Serum testosterone, leptin and insulin increased while uterine InsR/GLUT-4 expression decreased in L group indicating metabolic abnormalities. Endometrial hyperplasia, increased expression of PCNA and AR indicated abnormal proliferation in L compared to C. Increased uterine oxidative load (SOD/catalase/LPO) and inflammatory markers NFκB/COX-2 expression in L was responsible for high tissue oxidative stress and inflammation. M administration normalized all the above parameters suggesting its ameliorative effect in L + M group.

SIGNIFICANCE

We report PCOS induced uterine dysfunction in Mesocricetus auratus for the first time. M administration restores uterine functions modulating cellular dynamicity, metabolic status, decreased oxidative and inflammatory load in PCOS hamsters. Therefore, we suggest the therapeutic potential of M against PCOS led uterine abnormalities to restore female fertility.

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.

Increased pro-inflammatory cytokines in ovary and effect of γ-linolenic acid on adipose tissue inflammation in a polycystic ovary syndrome model

Polycystic Ovary Syndrome (PCOS), a major endocrine disorder, affects the reproductive function of a woman, along with an association with metabolic conditions like insulin resistance and inflammation. The inflammatory nature of PCOS is much debated over, owing to numerous cases of elevation in cytokine levels. Studies have shown the beneficiary effect of Gamma-Linolenic acid (GLA) in reducing inflammation related to many conditions such as atopic dermatitis, rheumatoid arthritis, arterial disease, obesity, and even PCOS. The study aims at assessing the expression of inflammatory cytokines in the ovary and Peri-ovarian adipose tissue (POAT) of the Dehydroepiandrosterone (DHEA) induced PCOS rat model. Further, this study also evaluates the effect of γ-linolenic Acid (GLA) on these cytokines in POAT. Female Wistar rats were subcutaneously injected with 60 mg/kg DHEA daily for 28 days. These PCOS-induced rats were then orally administered with 50 mg/kg GLA for 14 days. The gene expression of cytokines was assessed by Real Time-PCR. The study showed an increase in the expression of cytokines in the ovary and POAT of the DHEA group. This suggests the role of ovarian adipose in adding to the pro-inflammatory state of PCOS. Moreover, the administration of GLA to the PCOS-induced rats resulted in a reduction of cytokine expression from the POAT, indicating that the compound was successful in reducing the associated inflammation. The study throws light on the possibility of using GLA as a supplementary or naturalistic alternative in ameliorating ovarian adipose-associated inflammation that accompanies PCOS.

Sirtuins-The New Important Players in Women's Gynecological Health

The participation of sirtuins in the regulation of oxidative stress and inflammation lies at the basis of their possible modes of action and is related to their expression in various cell structures; their location in the mitochondria and blood plasma has been indicated as of primary importance. Despite many existing studies, research on sirtuins continues to present an opportunity to discover new functions and dependencies, especially when it comes to women's gynecological health. Sirtuins have a significant role in both the formation and the course of many gynecological diseases. Their role is particularly important and well documented in the course of the development of cancer within the female reproductive organs; however, disturbances observed in the ovary and oocyte as well as in follicular fluid are also widely investigated. Additionally, sirtuins take part in some gynecological disturbances as regulative factors in pathways associated with insulin resistance, glucose and lipids metabolism disorders. In this review, we would like to summarize the existing knowledge about sirtuins in the manner outlined above.

Polycystic ovary syndrome and endothelial dysfunction: A potential role for soluble lectin-like oxidized low density lipoprotein receptor-1

The aims of this study were to investigate whether serum soluble lectin-like oxidized low-density lipoprotein receptor-1 (sLOX-1), oxidized LDL (oxLDL), paraoxonase-1(PON-1) and hydroperoxide (LOOH) levels are altered in women with polycystic ovary syndrome (PCOS) and also to determine if hyperandrogenism, insulin resistance (IR) and Anti-Müllerian Hormone (AMH) are associated with endothelial dysfunction in PCOS. A total of 46 women with PCOS and 46 non-PCOS healthy controls were recruited. Women with PCOS had significantly higher sLOX-1, oxLDL and LOOH concentrations than non-PCOS women [6.16 (3.92-13.95) vs 1.37 (0.63-4.43) ng/mL, p < 0.001; 6.48 ± 1.03 vs 3.16 ± 1.02 μU/L, p < 0.001; 2.45 (1.45-3.45) vs 1.06 (0.64-1.56) μmol/L, p < 0.001]. The mean PON-1 level of PCOS group was lower than non-PCOS group (69.47 ± 10.75 vs 104.08 ± 21.43 U/mL, p < 0.001). There was no significant difference in terms of the sLOX-1, oxLDL, LOOH and PON-1 levels between normal weight and overweight PCOS women. On univariate logistic regression analysis, Ferriman-Gallwey scale (FGS), HOMA-IR and AMH were an independent predictors of high risk group of endothelial dysfunction markers (HR-EDm). Age and BMI were not associated with HR-EDm. When incorporated into the multivariate model, endotelial dysfunction markers independently correlated with clinical hyperandrogenism (FGS) but not with AMH. In conclusion, our results indicated that an increased concentration of sLOX-1 might be an early predictor of endothelial damage in patients with PCOS. Women with PCOS have elevated sLOX-1, oxLDL, LOOH and decreased PON-1 levels, independent of BMI. Endothelial dysfunction in women with PCOS is associated with hyperandrogenism. Further studies are required to confirm our findings.

Systemic adiponectin treatment reverses polycystic ovary syndrome-like features in an animal model

The present study examined the efficacy of adiponectin for regulating the reproductive, metabolic and fertility status of mice with polycystic ovary syndrome (PCOS). PCOS was induced in prepubertal (21- to 22-day-old) mice using dehydroepiandrosterone (6mg 100g-1day-1 for 25days), after which mice were administered either a low or high dose of adiponectin (5 or 15µgmL-1, s.c., respectively). PCOS mice exhibited typical features, including the presence of numerous cystic follicles, increased circulating androgens, increased body mass, altered steroidogenesis, decreased insulin receptor expression and increased serum triglycerides, serum glucose, Toll-like receptor (TLR)-4 (a marker of inflammation) and vascular endothelial growth factor (VEGF; a marker of angiogenesis). These parameters were significantly correlated with a reduction in adiponectin in PCOS mice compared with vehicle-treated control mice. Exogenous adiponectin treatment of PCOS mice restored body mass and circulating androgen, triglyceride and glucose levels. Adiponectin also restored ovarian expression of steroidogenic markers (LH receptors, steroidogenic acute regulatory protein and 3β-hydroxysteroid dehydrogenase), insulin receptor, TLR-4 and VEGF levels in control mice. Adiponectin restored ovulation in PCOS mice, as indicated by the presence of a corpus luteum and attainment of pregnancy. These findings suggest that adiponectin effectively facilitates fertility in anovulatory PCOS. We hypothesise that systemic adiponectin treatment may be a promising therapeutic strategy for the management of PCOS.

Polycystic ovary syndrome and mitochondrial dysfunction

Polycystic ovary syndrome (PCOS) is a prevalent hormonal disorder of premenopausal women worldwide and is characterized by reproductive, endocrine, and metabolic abnormalities. The clinical manifestations of PCOS include oligomenorrhea or amenorrhea, hyperandrogenism, ovarian polycystic changes, and infertility. Women with PCOS are at an increased risk of suffering from type 2 diabetes; me\tabolic syndrome; cardiovascular events, such as hypertension, dyslipidemia; gynecological diseases, including infertility, endometrial dysplasia, endometrial cancer, and ovarian malignant tumors; pregnancy complications, such as premature birth, low birthweight, and eclampsia; and emotional and mental disorders in the future. Although numerous studies have focused on PCOS, the underlying pathophysiological mechanisms of this disease remain unclear. Mitochondria play a key role in energy production, and mitochondrial dysfunction at the cellular level can affect systemic metabolic balance. The recent wide acceptance of functional mitochondrial disorders as a correlated factor of numerous diseases has led to the presupposition that abnormal mitochondrial metabolic markers are associated with PCOS. Studies conducted in the past few years have confirmed that increased oxidative stress is associated with the progression and related complications of PCOS and have proven the relationship between other mitochondrial dysfunctions and PCOS. Thus, this review aims to summarize and discuss previous and recent findings concerning the relationship between mitochondrial dysfunction and PCOS.

Low-Dose Tacrolimus Prevents Dysregulated Peri-Conceptional Ovarian and Systemic Immune Cellular Homeostasis in Subjects with PCOS

Polycystic ovary syndrome (PCOS) is characterized by failure of ovulation and is associated with obesity and chronic inflammation. Recent evidence suggests that anomalous activation of ovarian macrophages and numerical and functional deficits in the Th17 (CD4+IL17A+) and the CD4+CD25+CD127^low Tregs plays crucial role in PCOS. We have shown that the pre-pregnancy use of tacrolimus prevents adverse reproductive outcomes in a mouse model of PCOS. Here we used the HFD-NONcNZO mice to test a hypothesized beneficial use of tacrolimus relative to metformin in favorably influencing the ovarian and systemic immune milieux conducive to gestational success in subjects with PCOS. Compared to normative controls, our data revealed an aberrant peri-conceptional suppression of the CD4⁺CD25⁺CD127^low Tregs together with an overexpression of the Th17 T cells and lack of coordinated activation of ovarian macrophages in untreated HFD-dNONcNZO mice. Significant variances in treatment outcomes favoured the use of tacrolimus over metformin in treated mice. Consistent with the human fertility studies, this investigation reveals a beneficial systemic use of tacrolimus (0.1 mg/kg) in promoting early pregnancy in individuals with PCOS and suggests the need for further research into the selective inhibition of IL17A as a plausibly alternative immunotherapeutic approach in the clinical management of infertile individuals with PCOS.

Antioxidant effect of genistein on ovarian tissue morphology, oxidant and antioxidant activity in rats with induced polycystic ovary syndrome

Background

Oxidative stress is the most frequent cause of female infertility disorders including polycystic ovary syndrome (PCOS). Genistein as a major component of soybean isoflavone scavenges free radicals by antioxidant activities.

Objective

The present study examines the antioxidant effects of genistein on ovarian tissue following experimental PCOS in rats.

Materials and Methods

Twenty female Wistar rat were randomly divided into the following groups (n=5 each group): (I) control group (no treatment); (II) induced PCOS (injection of estradiol valerate); (III) genistein-treated non-PCOS (received genistein); and (IV) genistein-treated PCOS groups. The weight of rats were measured and the blood samples collected and centrifuged. The oxidant and antioxidant activity of plasma and ovaries were measured. All rats were sacrificed under anesthesia, and ovaries were collected and weighted. Histological examination and follicular quality were assessed by staining.

Results

In histological observation, the induced PCOS rats displayed more number of atretic follicles and the follicular quality in genistein-treated rats was similar to the control groups. The plasma and ovaries malondialdehyde levels significantly increased in PCOS rats (p < 0.001), while the total antioxidant capacity levels, glutathione peroxidase, and superoxide dismutase activities significantly decreased (p < 0.001). The plasma and ovary malondialdehyde levels significantly decreased in PCOS rats that were treated with genistein (p < 0.001) and the total antioxidant capacity (p < 0.05), glutathione peroxidase, and superoxide dismutase activities significantly increased (p < 0.001).

Conclusion

Treatment with genistein preserved follicular quality by increasing antioxidant activities and scavenging oxidant levels in PCOS rats.

Polycystic Ovarian Condition May Be a Risk Factor for Ovarian Tumor Development in the Laying Hen Model of Spontaneous Ovarian Cancer

Chronic inflammation and long-standing oxidative stress are potential predisposing factors for developing malignancies, including ovarian cancer (OVCA). Information on the association of ovarian chronic abnormal conditions, including polycystic ovarian syndrome (PCOS), with the development of OVCA is unknown. The goal of this study was to examine if polycystic ovarian conditions are associated with OVCA development. In the exploratory study, 3-4-year-old laying hens were randomly selected and examined for the presence of polycystic ovaries with cancer (PCOC). In the prospective study, hens were monitored by ultrasound scanning to detect the incidence of a polycystic ovaries and subsequent development of OVCA. Tissues from normal ovaries and PCOC were examined for macrophage infiltration, expression of interleukin-16, and superoxide dismutase 2. The exploratory study detected spontaneous PCOC at early and late stages in hens. PCOC in hens were accompanied with influx of macrophages (17.33 ± 2.26 in PCOC at the early stage and 24.24 ± 2.5 in PCOC at the late stage in 20 mm² areas of tissue as compared with 6.77 ± 1.58 in normal hens). Expression of interleukin-16 was more than 2.5-fold higher and superoxide dismutase 2 was approximately 3-fold higher in PCOC hens than normal hens. The prospective study showed the development of OVCA in some hens with polycystic ovarian condition (PCO). PCOC development in hens was associated with chronic inflammation in the ovary. Laying hens may represent a potential model for the study of spontaneous PCOS and its long-term risk of PCOC development.

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.

Oxidative stress and metabolic markers in pre- and postnatal polycystic ovary syndrome rat protocols

Background

Several studies have described an enhanced inflammatory status and oxidative stress balance disruption in women with polycystic ovary syndrome (PCOS). However, there is scarce information about redox markers in the blood of androgenized animal models. Here, we evaluated the serum/plasma oxidative stress marker and metabolic parameter characteristics of prenatal (PreN) and postnatal (PostN) androgenized rat models of PCOS.

Materials and methods

For PreN androgenization (n=8), 2.5 mg of testosterone propionate was subcutaneously administered to dams at embryonic days 16, 17, and 18, whereas PostN androgenization (n=7) was accomplished by subcutaneously injecting 1.25 mg of testosterone propionate to animals at PostN day 5. A unique control group (n=8) was constituted for comparison.

Results

Our results indicate that PostN group rats exhibited particular modifications in the oxidative stress marker, an increased plasma ferric-reducing ability of plasma, and an increased antioxidant capacity reflected by higher albumin serum levels. PostN animals also presented increased total cholesterol and triglyceride-glucose levels, suggesting severe metabolic disarrangement.

Conclusion

Study findings indicate that changes in oxidative stress could be promoted by testosterone propionate exposure after birth, which is likely associated with anovulation and/or lipid disarrangement.

Evaluation of pro-oxidant-antioxidant balance (PAB) and its association with inflammatory cytokines in polycystic ovary syndrome (PCOS)

Chronic low-grade inflammation has been suggested as a key contributor of the pathogenesis and development of polycystic ovary syndrome (PCOS). To investigate the association between oxidative stress status and inflammatory cytokines in follicular fluid of 21 PCOS women compared to 21 women with normal ovarian function who underwent intra-cytoplasmic sperm injection. Concentration of IL-6, IL-8, IL-10, and TNF-α was measured using sandwich ELISA. Oxidative stress was examined by measuring total oxidant status (TOS), malondialdehyde (MDA), total antioxidant capacity (TAC), and thiol groups. PCOS women had an elevated concentration of MDA and TOS compared to controls. Levels of TAC and thiol groups were lower in PCOS compared to controls. PCOS patients had a higher concentration of IL-6, IL-8, and TNF-α compared to controls. Concentration of IL-10 was lower in PCOS compared to controls. Significant correlations were found between MDA and TOS concentration with TNF-α and between IL-6 and MDA, IL-8 and TAC, IL-10 and TOS levels and also between IL-10 and TAC levels. TAC and thiol groups were negatively correlated with TNF-α. Increased oxidative stress in PCOS is associated with inflammation which is closely linked. Inflammation can induce production of inflammatory cytokines in this syndrome and directly stimulates excess ovarian androgen production.