The use of dehydroepiandrosterone-treated rats is not a good animal model for the study of metabolic abnormalities in polycystic ovary syndrome

Testosterone, sex hormone-binding globulin and dehydroepiandrosterone levels and cervical length of Egyptian women with a history of recurrent miscarriages, polycystic ovary syndrome and without the conditions at three stages of pregnancy

Total testosterone (TT), sex hormone-binding globulin (SHBG), dehydroepiandrosterone (DHEA) levels, and cervical length (CL) were investigated in pregnant Egyptian women with polycystic ovary syndrome (PCOS, n = 38), history of miscarriages (RM, n = 40) and without the conditions (HC, n = 40). At week 8, the RM had lower levels of TT (p = 0.000) and free androgen index (FAI) (p = 0.000) and higher SHBG (p = 0.000) and DHEA (p < 0.05) than the PCOS. Compared with the HC, they had elevated SHBG (p < 0.05) and DHEA (p = 0.001) and reduced CL (p = 0.000). TT (p = 0.001) and FAI (p = 0.000) were higher and SHBG (p = 0.000) and CL (p = 0.001) lower in the PCOS than in the HC group. At week 16, TT (p = 0.000) and FAI (p = 0.000) were higher, and SHBG (p = 0.000) and CL (p < 0.05) lower in PCOS than in RM and HC. The PCOS had elevated FAI than the RM (p = 0.000) and HC (p = 0.001) at week 20. The DHEA, SHBG and CL abnormalities in PCOS and RM may compromise pregnancy outcomes.IMPACT STATEMENTWhat is already known on this subject? Hyperandrogenaemia, low sex hormone-binding globulin (SHBG), shortened cervical length (CL) and polycystic ovary syndrome (PCOS) are the most cited risk factors for recurrent miscarriages (RM). However, the published data are inconsistent, perhaps because of the confounding effects of ethnicity and nutritional milieu.What do the results of this study add? The study's findings comprising ethnically and socially homogenous women demonstrate that PCOS and RM are characterised by elevated dehydroepiandrosterone (DHEA) and shortened CL, and PCOS by reduced SHBG. These abnormalities would be expected to have an adverse impact on pregnancy outcomes.What are the implications of these findings for clinical practice and/or further research? Twenty-weeks DHEA and CL values have the potential to predict outcome risk in women with a history of RM and PCOS. Further research on other population groups is required to validate the current study's findings.

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.

The Effect of Hydroalcoholic Calendula Officinalis Extract on Androgen-Induced Polycystic Ovary Syndrome Model in Female Rat

Background. Polycystic ovary syndrome (PCOS) is the most common hormonal disorder in women of reproductive age, and the major cause of infertility. Today, using medicinal plants instead of chemical drugs could be an alternative treatment option for PCOS. The purpose of this study was to determine the effect of Calendula officinalis hydroalcoholic extract on PCOS in rats. Method. 60 female adult rats were randomly divided into six groups, including control, sham, PCOS group, and treated PCOS groups receiving hydroalcoholic extract of Calendula officinalis with different dosages of 200, 500, and 1000 mg/kg. PCOS was induced by subcutaneous injection of DHEA 6 mg/100 g bw for 35 days. For two weeks, the extract was taken orally. The serum glucose, insulin, sex hormone levels, and oxidative status were measured at the end of the experiment. The ovaries were dissected for histomorphometric and pathological analysis. Results. When compared to the control and sham groups, the PCOS group showed a significant increase in glucose, insulin, testosterone, and malondialdehyde (MDA) concentrations, cystic and atretic follicles, and thickness of the theca and tunica albuginea layers, and a significant decrease in LH concentration, total antioxidant capacity, corpus luteum, antral follicles, and oocyte diameter. The mean concentration of FSH, on the other hand, did not change significantly. A trend of improvement was found in the treated groups with high doses of Calendula officinalis extract. Conclusion. In rats with PCOS and nonovulation, Calendula officinalis hydroalcoholic extract improved oxidative stress, restored folliculogenesis, and increased ovulation.

Polycystic Ovary Syndrome: Insights from Preclinical Research

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, affecting approximately 10%. PCOS is diagnosed by the presence of at least two of these three criteria: hyperandrogenemia, oligo- or anovulation, and polycystic ovaries. The most common type (80%) of PCOS includes hyperandrogenemia. PCOS is also characterized by obesity or overweight (in 80% of US women with PCOS), insulin resistance with elevated plasma insulin but not necessarily hyperglycemia, dyslipidemia, proteinuria, and elevated BP. Although elevated compared with age-matched controls, BP may not reach levels considered treatable according to the current clinical hypertension guidelines. However, it is well known that elevated BP, even modestly so, increases the risk of cardiovascular disease. We have developed a model of hyperandrogenemia in rodents that mimics the characteristics of PCOS in women, with increases in body weight, insulin resistance, dyslipidemia, andproteinuria and elevated BP. This review discusses potential mechanisms responsible for the elevated BP in the adult and aging PCOS rat model that may be extrapolated to women with PCOS.

Cysteine-Cysteine Motif Chemokine Receptor 5 Expression in Letrozole-Induced Polycystic Ovary Syndrome Mice

Polycystic ovary syndrome (PCOS), which affects 5–10% of women of reproductive age, is associated with reproductive and metabolic disorders, such as chronic anovulation, infertility, insulin resistance, and type 2 diabetes. However, the mechanism of PCOS is still unknown. Therefore, this study used a letrozole-exposed mouse model in which mice were orally fed letrozole for 20 weeks to investigate the effects of letrozole on the severity of reproductive and metabolic consequences and the expression of cysteine–cysteine motif chemokine receptor 5 (CCR5) in letrozole-induced PCOS mice. The letrozole-treated mice showed a disrupted estrous cycle and were arrested in the diestrus phase. Letrozole treatment also increased plasma testosterone levels, decreased estradiol levels, and caused multicystic follicle formation. Furthermore, histological analysis of the perigonadal white adipose tissue (pgWAT) showed no significant difference in the size and number of adipocytes between the letrozole-treated mice and the control group. Further, the letrozole-treated mice demonstrated glucose intolerance and insulin resistance during oral glucose and insulin tolerance testing. Additionally, the expression of CCR5 and cysteine-cysteine motif ligand 5 (CCL5) were significantly higher in the pgWAT of the letrozole-treated mice compared with the control group. CCR5 and CCL5 were also significantly correlated with the homeostasis model assessment of insulin resistance (HOMA-IR). Finally, the mechanisms of insulin resistance in PCOS may be caused by an increase in serine phosphorylation and a decrease in Akt phosphorylation.

Challenges in Establishing a Relevant Model of Polycystic Ovary Syndrome in Rats – A Mini Review

Polycystic ovary syndrome (PCOS) is one of the most com-mon female endocrinopathy and one of the leading causes of in-fertility. However, the exact etiopathogenetic mechanisms are not discovered yet, while therapeutic strategies in PCOS commonly rely on symptomatic rather than curative. Regarding reasonable ethical limitations in human population, animal experimental studies can provide better insights into mechanisms underlying etiopathogenesis of PCOS, as well as investigations of different therapeutic strategies. Rodent models for PCOS are very useful for experimental studies due to their great genetic similarities with human genome, short reproductive and life span, feasible gener-ating of genetically adapted animals, and convenient and acces-sible use. To our knowledge, androgens (dehydroepiandroste-rone, testosterone propionate, 5a-dihydrotestosterone), as well as estradiol valerate, represent the most frequently used hormones for PCOS modeling. Furthermore, the administration of antipro-gesterone or letrozole has been reported as effective for PCOS induction. In our review, the presented PCOS models were ac-complished by the administration of different hormones or drugs and alterations of environment. The main focus of this review was to summarize the alterations in ovarian morphology, hypotha-lamic-pituitary-ovarian axis, and hormone levels across above-mentioned protocols for postnatal PCOS modeling in rats.

Morphological changes in the experimental model of polycystic ovary syndrome and effects of vitamin D treatment

AIM

This research was designed to develop an animal model by inducing polycystic ovary syndrome (PCOS) with dehydroepiandrosterone (DHEA) and observe reproductive and morphological changes after treatment with vitamin D.

MATERIALS AND METHODS

Thirty pre-pubertal female Sprague-Dawley (SD) dams were recruited. The animals were distributed 10 each in control, PCOS and vitamin D-treated groups. In control group 0.2 ml of sesame oil was given. PCOS group was administered DHEA by the daily dose of 6 mg/kg for 30 days. In vitamin D-treated group, animals were injected 6 mg/kg/day DHEA daily and 120 ng 1, 25(OH) 2D3/100 g subcutaneously once a week. The occurrence of reproductive phenotypic PCOS was evaluated by estrous cycle, morphology and histological changes of ovary, uterus on light microscope.

RESULTS

The results of this study showed significant weight gain, obesity, and estrous irregularity in PCOs group as compared to control and vitamin D-treated group.

CONCLUSION

Administration of vitamin D (120 ng 1, 25(OH) 2D3/100) improved the cycle characteristics, reduced body weight and morphological features in PCOS induced animals. The results support the effect of vitamin D treatment for metabolic and reproductive characteristic features in PCOS females.

Curcumin-loaded super-paramagnetic iron oxide nanoparticle affects on apoptotic factors expression and histological changes in a prepubertal mouse model of polycystic ovary syndrome-induced by dehydroepiandrosterone - A molecular and stereological study

AIMS

This study investigated the effects of curcumin-loaded super-paramagnetic iron oxide (Fe₃O₄) nanoparticles (NPs) (SPIONs) on histological parameters and apoptosis-inducing factors (AIFs) in an experimental mouse model of polycystic ovary syndrome (PCOS).

MATERIALS AND METHODS

A total number of 40 female prepuberal BALB/c mice were randomly divided into four groups. Group 1 was selected as control and Group 2 was considered as a vehicle taking sesame oil, in the form of a curcumin carrier. Moreover, Group 3 was administered with dehydroepiandrosterone (DHEA) at 6 mg/100 g of the body weight and Group 4 received the DHEA plus the NPs of curcumin (5.4 mg/100 g) for twenty consecutive days. Finally, histology, stereology, and apoptosis of the ovary were evaluated.

KEY FINDINGS

The results revealed that the NPs of curcumin had reduced ovarian volume (p < 0.05) and a total number of primary, secondary, antral, and primordial follicles in comparison with the PCOS and vehicle groups (p < 0.05). Furthermore, curcumin treatment following administration of the DHEA resulted in a significant decrease in BAX (p < 0.001) and levels of expression of Caspase3 (CASP3) protein, increased levels of B-cell lymphoma 2 (Bcl2) expression (p < 0.05), and moderated apoptosis in granulosa cells in comparison with the ones seen in the PCOS group.

SIGNIFICANCE

Ovarian injuries and DHEA-induced apoptosis were efficiently suppressed by curcumin, indicating the probable protective property of NPs of curcumin against PCOS.