Ovarian Activity Research Articles

Quality improvement project in primary care to improve management of women with premature ovarian insufficiency

Background: Premature Ovarian Insufficiency (POI) is defined as the loss of ovarian activity before the age of 40 years. The prevalence in the general population is an estimated 1% in the UK. If untreated, POI can cause serious long term health consequences, including increased risk of cardiovascular disease, osteoporosis, impaired cognition, reduced psychological wellbeing, and quality of life. To lower the risk of these, hormone replacement therapy (HRT) is advised until the natural age of the menopause. Investigations are recommended by ESHRE to look at primary causes as well as a baseline DEXA scan. We present results from a study exploring prevalence, diagnosis, and management of POI in an urban Primary Care Practice in East London.

The GnRH analogue Decapeptyl was able to induce ovulation in cyclic jennies

The aim of this study was to assess the ability of the GnRH analogue decapeptyl to induce ovulation of jennies in oestrus. Most of the northern hemisphere donkey breeds are faced with the risk of extinction (Camillo et al. J Equine Vet Sci 2018;65:44-49), thus donkey reproduction is considered an emerging branch of theriogenology and the management of induction of ovulation is a crucial point to set up preservation protocols (Carluccio et al. Theriogenology 2007;68:914-919; Camillo et al. Anim Reprod Sci 2014;151:56-60). In this study six Amiata jennies aged between 3 and 10 years, cyclic, in good general health and with a body condition score of ¾ were employed (Vall et al. in: Pearson, et al. Ed., 2003:93–102). For four consecutive cycles, jennies’ ovarian activity was routinely monitored; ultrasound examination was performed daily from the evidence of a follicle diameter ≥27 mm until ovulation. Upon reaching a follicular diameter ≥32±2 mm (hour 0), estrous jennies were treated alternatively with 100 mg Decapeptyl, sc, (DEC) or the equivalent volume of saline, sc, (CTRL) and examined ultrasonographically at hours 14, 24, 38, 42, 48, 62 and every 24 hours until ovulation. The experimental design was a 2 × 2 (with two replicates) Latin square. Induction of ovulation was considered successful if ovulation occurred between hours24 and 48 from treatment. An independent sample Student T Test and a Fisher Exact Test were performed to compare mean ovulation hour and ovulatory rates between DEC and CTRL groups, respectively. A forward stepwise multivariable logistic regression model based on the Wald statistics criterion of a P value smaller than 0.05 was used to establish significant predictors (group, jenny, and cycle number) for ovulation after treatment. Eleven/12 and 12/12 cycles resulted in ovulation for DEC and CTRL groups, respectively. Mean±SD ovulation time after treatment was 47.1±21.0 and 66.8±25.9 hours for DEC and CTRL respectively (P=0.059). Ovulation rates between 24h and 48h were 10/12 (83.3%) and 2/12 (16.7%) for DEC and CTRL respectively (P=0.003). Decapeptyl-treated jennies had a 25 times higher probability to ovulate between hours 24 and 48 than controls (P=0.003), while there were no jenny and cycle effects on the ovulatory rate. The results of this study show how Decapeptyl successfully induced ovulation in jennies, similarly to other GnRH analogs previously evaluated (Canisso et al. Vet Clin North Am Equine Pract 2019;35:607-642). Acknowledgments: The authors are grateful to Ente Terre Regionali Toscane for funding and for providing the jennies.

Possible involvement of somatotrophic hormones in the postpartum regulation of ovarian activity in mares

In horses, resumption of ovarian function after parturition occurs early and the majority of mares ovulate within two weeks after parturition. Previous research suggests that early postpartum increases in the peripheral concentration of prolactin and somatotrophic hormones are the major stimulus for resumption of ovarian activity and ovulation. In the present study, we investigated if placental tissue may be a source of somatotrophic hormones and thus influence ovarian activity. Ovarian follicular development and concentrations of prolactin, insulin like growth factor-1 (IGF1) and LH were determined in 14 healthy Haflinger mares (9.2±3.8 years). From D15 before until D15 after parturition (pp), transrectal ultrasonography of ovarian activity was performed and blood samples were collected for determination of hormone concentrations (prolactin, IGF1 by ELISA; LH by RIA). All foals were healthy, mature and stayed with their dams. Samples from the allantochorion and amnion were obtained immediately after delivery. The relative abundance of mRNA for IGF1 and the prolactin receptor (PRLR) was analyzed by qPCR. Formalin fixed samples were analyzed for protein expression of IGF1 and PRLR by immunohistochemistry. Statistical analysis (IBM SPSS 27.0) was done by analysis of variance (for repeated measures) comparing data from mares that ovulated(group ov; n=5) and did not ovulate until D15 pp (group non-ov, n=9). Values are mean ± SD. Mares from group ov foaled later in the year than non-ov mares (day of year 84±29 vs. 50±20, p<0.05), but no differences in gestation length, placental weight or size were detected. Already on D15 before parturition, ovarian follicles <2 cm diameter were present in all mares, but growth to preovulatory size occurred only pp with a higher growth rate in ov mares (day x group p<0.05). Prolactin and IGF1 concentrations increased from D5 before parturition, peaked at D1 pp (ov vs. non-ov: prolactin 13.0±6.3 vs. 7.9±4.4 ng/ml, p<0.05; IGF1 409±71 vs. 350±65 ng/ml, p<0.05) and declined thereafter. The LH concentration increased from D1 pp in group ov (D12 pp: 23.82±15.96 ng/ml) but not in non-ov (D12 pp: 10.82±5.26 ng/ml; day x group p<0.001). There was a high abundance of mRNA and protein for IGF1 and PRLR in placental tissue irrespective of group. In conclusion, ovarian follicles are detectable before foaling, but develop to preovulatory size only pp when prolactin and LH concentrations increase. In agreement with the situation in cattle, IGF1 stimulates ovarian activity in lactating mares. Placental tissue produces IGF1 that may be under the influence of prolactin as suggested by the presence of PRLR in both amnion and allantochorion.

Efeitos de lipopolissacarídeos na ativação e apoptose de folículos ovarianos primordiais em novilhas

ABSTRACT The objective of the present study was to evaluate the effect of lipopolysaccharide (LPS) administration on activation and apoptosis of primordial follicles. There was no difference in the total number of follicles as well as in the different types of follicles. Furthermore, the LPS challenge didn’t modulate the expression of genes related with ovarian reserve (HAM), oocyte survival (Survivin), activation rate (Pten, KIT, KITL1, KITL2, AKT1, SIRT1), and follicular abnormalities. Therefore, the LPS exposure with 24h interval had no effect on activation rate and primordial follicles abnormalities, and also had no effect on expression of anti-apoptotic genes and genes related with ovarian reserve, oocyte survival, activation rate, and primordial follicles abnormalities.

Immunohistochemical localization of kisspeptin and kisspeptin receptor in the equine ovary: Effect of follicle size and reproductive state

Kisspeptin is considered a regulator of reproduction by stimulating GnRH; however, extra-hypothalamic actions of kisspeptin have been described. The aim of this study was to localize kisspeptin-10 (Kp10) and kisspeptin receptor (Kiss1r) in the ovary and compare staining intensity between follicles in follicular-phase (FP) and luteal-phase (LP) ovaries, as well as between seasonally anovulatory (SA) ovaries and ovaries from mares induced to cycle in winter with estradiol cypionate (ECP) and sulpiride. Eight ovaries were collected from light-horse mares during the breeding and non-breeding seasons and characterized as FP (n = 3), LP (n = 2), or SA (n = 3). Additionally, 3 ovaries were collected from SA mares treated with ECP and sulpiride upon detection of the first 30-mm follicle after treatment. Immunohistochemistry was carried out on whole-ovarian, paraffin-embedded sections using anti-Kp10 and anti-Kiss1r antibodies validated on equine hypothalamus. Staining intensity was evaluated in primordial, preantral, and antral follicles using a scale of 0-3. Given a normal distribution, two-way ANOVA was used to compare staining between follicle sizes and reproductive states. Staining for Kp10 and Kiss1r was detected in all follicle sizes throughout all reproductive states, as well as in oocytes and corpora lutea. Staining intensity for both differed between all follicle sizes and was greatest (P < 0.01)in antral follicles. Staining for Kp10 and Kiss1r was similar in preantral follicles of all reproductive states but was greater (P < 0.01) than primordial follicles. In primordial follicles, staining for Kp10 and Kiss1r was greatest (P < 0.01) in ECP-sulpiride stimulated ovaries, but similar between all other states. Kisspeptin-10 and Kiss1r staining was greatest (P < 0.01) in antral follicles of FP and ECP-sulpiride stimulated ovaries. Additional quantification of Kp10 and Kiss1r immunostaining in granulosa cells (GC) of antral follicles was achieved by evaluating three random, 625 μm2 fields in 2-3 follicles per animal in each reproductive state. Color deconvolution of standardized images was performed, and units of intensity converted to optical density and compared by ANOVA. Staining for both Kp10 and Kiss1r was most intense in GC of FP and ECP-sulpiride-stimulated ovaries and was greater (P < 0.0001) than LP and SA ovaries. No differences were detected between LP and SA. Here we characterize, for the first time, Kp10 and Kiss1r in the equine ovary. Staining intensity for both increased as follicle size increased. Staining was greatest in GC of FP ovaries, indicating a potential mechanistic role for kisspeptin during late-stage follicle growth and perhaps ovulation. Furthermore, staining in ECP-sulpiride stimulated ovaries was similar to FP ovaries, providing evidence that treatment with ECP-sulpiride during seasonal anovulation restored ovarian kisspeptin activity to a FP-like state.

Factors affecting pregnancy rates in acyclic recipient mares prepared with an intravaginal progesterone device

In acyclic embryo recipient mares, artificial cycle protocols are conventionally based on estradiol followed by long acting (LA) progesterone injections. The use of intravaginal devices has been encouraged because it allows a rapid resynchronization of recipients (Rigoleto-Júnior et al., Journal of Equine Veterinary Science 2021; 97:103325) and days of estradiol injections have also been discussed (Silva et al., Journal of Equine Veterinary Science 2021; 103:103669), but further studies are needed to develop more appropriate protocols. The present work aimed to evaluate factors that affect fertility in a commercial ET program. A total of 114 healthy mares (5-15yr-old) were used as embryo recipients and divided into two groups according to ovarian activity: cyclic (n=57) and acyclic (n=57, anestrus or transitional). Day-0 was defined as the day of ovulation in the cyclic group and the day of a 1g intravaginal P4 device (iP4) insertion in the acyclic group. Before iP4 insertion, 17β-estradiol doses varied from 0 to 10mg daily depending on the presence of natural or induced uterine edema that ranged from 3 to 7 days in duration. A one-by-one Pearson's Chi-square test was used to compare pregnancy rates between groups and the effects on pregnancy rate of 1) number of days of 17β-estradiol injections, 2) uterine edema (0-4 score)on D0 in the acyclic group, and 3) day of ET in both groups. Plasma P4 concentrations were evaluated daily by RIA in acyclic (n=10) and cyclic (n=13) mares from D0 to D7. Repeated measure models followed by Tukey's test were used to compare mean plasma P4 within groups. Pregnancy rates did not differ between acyclic (82%, 47/57) and cyclic (75%, 43/57) mares (P=0.5). Uterine edema on Day 0 (P=0.7) and day of ET (P=0.05) did not affect pregnancy rates of acyclic mares. Three days of estradiol treatment in acyclic mares resulted in a lower pregnancy rate (P=0.0425) than four days of injections. For cyclic recipient mares, day of ET affected pregnancy rates (P=0.0001) where D4 (96%, 26/27) showed higher pregnancy rates than D5 (66.7%, 12/18) and D6-7 (41.7%, 5/12), but D5 and D6-7 did not differ. Mean plasma P4 concentrations varied over days for both groups (P>0.05). In cyclic mares, mean plasma P4 increased daily to D5 (plasma P4 = 10ng/mL) followed by a plateau, whereas in the acyclic group, iP4 insertion caused an abrupt rise in plasma P4 concentration within 24h (plasma P4=5.67mg/mL) followed by a gradual daily fall to D7 (plasma P4=2.78mg/dL). In conclusion, the use of acyclic recipient mares prepared with iP4 results in similar pregnancy rates as in cyclic mares despite differences in the plasma P4 profile.

Effects of different semen extenders on sperm motility and pregnancy rates in donkeys

Semen quality is highly associated with the success of artificial insemination (AI). The characteristics of semen preserved at room temperature will be influenced by various factors. The semen extender provides sufficient energy for sperm, maintains pH and osmotic pressure stability, inhibits the reproduction of microorganisms and thus prolongs the survival time of sperm. We investigated effects of extender type on semen motility and pregnancy rates in donkeys. Five Yangyuan jacks and 1000 Yangyuan jennies were included in the study. Semen was collected by artificial vagina and filtered to remove impurities. The sperm motility (i.e., total and progressive) and concentration were determined by computer-assisted sperm analysis. Biggers, Whitter and Whittingham (BWW), Brackett and Oliphant medium (BO), Human Tubal Fluid (HTF) and Beltsville Thawing Solution (BTS), were semen extenders from other animal species, CAU-A and CAU-B were diluents independently developed by our laboratory. Firstly, the semen was diluted with CAU-B in a ratio of 1:2 (v/v, sperm: CAU-B). After mixing, the semen was centrifuged at 1500rpm for 10 min. The precipitation was retained and added to each tube. Then, the prewarmed extenders were slowly added along the tube wall and mixed by gentle shaking. After cooling to 17°C, diluted semen was placed in an incubator, mixed every 8h, and the sperm motility was analyzed. Meanwhile, we used transrectal palpation andB-mode ultrasound to determine ovarian activity of jennies. Upon detection of a 30-35 mm follicle, jennies were treated with the GnRH analogue deslorelin (GnRH-D) and inseminated with fresh semen diluted appropriately. The pregnancy rate of jennies was evaluated 20 days after ovulation. Statistical analysis was performed by ANOVA. Values are given as mean ± standard error. When diluted semen was stored at 17°C, the motility decreased with the increase of storage time extender. After 16h, sperm in BWW, BTS, BO and HTF extender were all dead. After 48h storage, the motility of sperm in CAU-A (mean 36.14 ± 6.12%) was lower (p < 0.05) than that in CAU-B (53.87 ± 16.25%). Pregnancy rates after insemination with semen diluted in CAU-A, CAU-B, BWW and BO were 30.53%, 34.77%, 29.37% and 30.96%, respectively, and there was no significant difference among groups (p>0.05). However, the pregnancy rate of semen diluted by CAU-B, which contains raffinose and fructose was slightly higher than that of the other groups. In conclusion, the results show that extension of donkey semen in CAU-B extender resulted in a slightly although not significantly improved pregnancy rate. This suggests that the semen extender is important for both, sperm viability and fertilization. This finding may be of significance for breeding and reproduction of donkeys and other equid species.

The opioid peptide leucine-enkephalin disrupts seasonal and gonadotropin-induced ovarian recrudescence in the gecko Hemidactylus frenatus

The enkephalins are known to regulate many physiological functions, including reproduction in vertebrates. However, the role of leucine-enkephalin (L-ENK) in the ovarian recrudescence activity of reptiles is not known. In the present study, we studied the influence of L-ENK on seasonal and FSH–induced ovarian recrudescence during the breeding and non-breeding phases of the cycle in the tropical and subtropical gecko Hemidactylus frenatus. In the first experiment, treatment with 5 and 25 μg L-ENK resulted in a dose-dependent inhibitory effect on the hypothalamic gonadotropin-releasing hormone (GnRH) neurons and ovary, as indicated by a significantly decreased percent area of GnRH-immunoreactive (GnRH-ir) fibres in the median eminence and pars distalis of the pituitary gland, concomitant with complete absence of stage V (late vitellogenic) follicles in the ovary compared to those of experimental controls. In the second experiment, administration of FSH to lizards in the regression phase stimulated the recruitment of stage IV and V (vitellogenic) follicles in contrast to their absence in initial controls or treatment controls. However, similar treatment of FSH in combination with 25 μg L-ENK did not result in the development of stage IV or V follicles. Together, these results suggest for the first time that treatment with 5 and 25 μg L-ENK exerts a dose-dependent inhibitory effect on the hypothalamic GnRH release into the median eminence and pituitary gland, leading to the blockade of ovarian recrudescence. These results also suggest a possible direct inhibitory effect of L-ENK at the level of the ovary in the gecko.

Reduction of ovarian reserves and activation of necroptosis to in vivo air pollution exposures

ABSTRACT We investigated the association between air pollution and changes in ovarian follicles, anti-mullerian hormone (AMH) levels, the occurrence of necroptosis cell death by activation of receptor-interacting protein kinase 3 (RIPK3) and, the activation of mixed lineage kinase domain-like (MLKL) proteins. Forty-two female Wistar rats were divided into three groups of 14 each, which were exposed to real-ambient air, filtered air and purified air (control) in two periods of 3 and 5 months. The results showed that the number of ovarian follicles decreased in the group exposed to real-ambient air versus the control group (P < 0.0001). The trend of age-related AMH changes with respect to exposure to air pollutants was affected and its levels decreased after 3 months of exposure. The MLKL increased in the group exposed to the real-ambient air compared to the control group (P = 0.033). Apparently long-term exposure to air pollution can reduce ovarian reserves.

Effects of different photoperiods on growth and ovarian development and maturation of silver pomfret Pampus argenteus.

Photoperiod has a great influence on the growth and ovarian development and maturation of fishes. To analyse the effects of photoperiod on growth and ovarian development of an important marine economic fish, silver pomfret Pampus argenteus, short photoperiod group (L:D = 8:16), control group (L:D = 12:12) and long photoperiod group (L:D = 18:6) were set up for 60 days. The growth performance, ovarian development, changes in hormones and key enzyme activities in the hypothalamic-pituitary-gonadal (HPG) axis and expressions of key regulatory genes in the HPG axis were studied under different photoperiod conditions. The results showed that the final weight gain, body weight index, specific growth rate for weight, specific growth rate for length and average daily growth were the highest in the long photoperiod group, and the feed conversion rate was the lowest. Under long photoperiod condition, gonado-somatic index and hepato-somatic index were higher, ovarian maturity was better and expressions of HPG axis-related regulatory genes foxl2a, foxl2b, cyp19a1a, cyp19a1b, kiss, gpr54-2, gnrh2, fsh and lh were higher. When compared with the other two groups, in the long photoperiod group, the change trend of estradiol (E2) was consistent with those of luteinizing hormone, melatonin (MT) and kisspeptin, and the levels were higher on the 20th and 50th days. These results indicate that prolongation of the photoperiod can improve the growth performance of P. argenteus and promote ovary development and maturation. The authors speculate that photoperiod may regulate the ovarian activity of P. argenteus through MT and kisspeptin/gpr54 signalling pathways. The results show that photoperiod can regulate the ovarian development of P. argenteus, which would help in breaking the seasonal restrictions of animals and regulating an animal's reproductive cycle.

139 Cyclic changes in uterine epithelial sodium channel in mares

Epithelial sodium channel (ENaC) has been localized within many organs of various species, including the uterus of mice, rats, and humans. Additionally, ENaC expression within the rodent uterus was differentially influenced by 17β-estradiol (E2) and progesterone (P4), and has been proposed to be the major mechanism regulating uterine fluid absorption and secretion. In the equine, ENaC has been observed in the trachea, hooves, and endometrium; however, the potential relationship between E2, P4, and ENaC in the mare endometrium has yet to be elucidated. The aim of this study was to investigate possible interactions between E2, P4, and ENaC from cycling mares using immunohistochemistry (IHC). Estrus was synchronized for all mares (n = 13) by daily administration of oral altrenogest (ALT) for 15 consecutive days. On the last day of ALT treatment, all mares received 5 mg of dinoprost IM. Following synchronization, all mares were teased daily with a stallion. Transrectal ultrasonography (US) for observation of ovarian activity and day of ovulation (OV; d0) were completed every other day until OV. On d10, US, blood collection via jugular venipuncture, and a uterine biopsy sample were collected. Biopsy samples were fixed to later complete ENaC evaluation by IHC. A uterine biopsysample and blood collection had also been similarly collected and processed for each mare during estrus when she simultaneously had a ≥ 30mm Graafian follicle present and was displaying estrual behaviors. For statistical comparison, a paired t-test was applied. Mares averaged an estrus duration of 4.85 ± 1.86 d. Plasma E2 was 2.27 ± 0.45 pg/mL on d10 and 3.58 ± 0.48 pg/mL on estrus sample day. Plasma P4 concentration was significantly higher (P < 0.01) on d10 when compared with estrus sample day (8.53 ± 1.17 ng/mL vs 0.04 ± 0.02 ng/mL, respectively). The percentage of positively stained ENaC cells was significantly higher (P < 0.01) on d10 when compared with estrus sample day (81.27 ± 3.19% vs 58.84 ± 3.23%). In conclusion, our findings indicate that sex steroids, specifically P4, may regulate ENaC within the mare endometrium, with ENaC being increased during diestrus and decreased during estrus. Collectively, the changes of ENaC concentrations during the estrous cycle might impact the critically sensitive fluid environment within the mare uterus.

Focused nutrition during oestrus synchronization in Pelibuey ewes with different body conditions

The aim of this study was to evaluate ovarian follicular activity, ovulation percentage, and body weight change in response to focused nutrition during synchronization of oestrus with an intravaginal device (CIDR®) (9 days) in Pelibuey ewes with high and low body condition. Seventy-two non-pregnant ewes without offspring were randomly distributed to one of four treatments, namely T1: (n = 18) ewes without focused nutrition and low body condition; T2: (n = 18) ewes without focused nutrition and high body condition; T3: (n = 18) ewes with focused nutrition and low body condition; and T4: (n = 18) ewes with focused nutrition and high body condition. While the CIDR device was in place, the ewes with focused nutrition received a supplement of 1.5 kg ewe/day, which contained 2.9 MCal metabolizable energy, 16% crude protein, 88.5% dry matter, 11.8% crude fibre, and 6.7% of ash. The concentration of progesterone (P4) was measured to determine ovulation percentage. The follicular population was quantified (2–3 mm, 4–5 mm, and &gt;6 mm in diameter). The number of follicles between 2–3 mm and 4–5 mm in diameter was similar among treatments. The number of follicles &gt;6 mm in diameter was higher in T4 ewes (2.2 ± 0.2) compared with T1, T2, and T3. The response to oestrus, the onset of oestrus, and the ovulation percentage were similar among treatments. Focused nutrition increased the number of ovarian follicles &gt;6 mm in diameter in ewes with high body condition.

Sustained-release deslorelin acetate implants disrupt oestrous cyclicity in the mare.

There is a need for a safe, effective and practical method of oestrus suppression in the mare. The aim of this study was to monitor ovarian activity in mares exposed to either 9.4 or 28.2 mg deslorelin acetate, a GnRH agonist, in the form of a sustained-release implant. Following oestrus synchronisation, mares were randomly assigned to one of three groups (n = 4 per group) and administered either one (Des1 group; 9.4 mg) or three (Des3 group; 28.2 mg) implants of deslorelin acetate (Suprelorin-12, Virbac Australia) or one blank implant (Control group; Virbac Australia). Mares underwent weekly blood sampling for 12 weeks following implant placement (Day 0-Day 84), with transrectal palpation and ultrasonography of the reproductive tract at all sampling timepoints except Days 56, 70 and 77. All mares showed baseline serum progesterone concentrations (SPC; ≤1.3 nmol/L or 0.4 ng/ml) on Day 0. Cycling Control mares showed typical oestrous cyclicity characterised by peaks and troughs in SPC over time. Four of eight treated mares demonstrated a sustained elevation in SPC after the initial ovulation after implant placement; SPC declined to baseline levels (Des1 group; 2 mares) or remained elevated (Des3 group; 2 mares) at the final sampling timepoint on Day 84. Oestrous cyclicity was erratic in three of the remaining four treated mares. In total, 87.5% (7 of 8) of treated mares showed atypical oestrous cyclicity after implant placement. These results suggest that deslorelin acetate disrupts oestrous cyclicity in the mare, which warrants further research.

Lovastatin, an Up-Regulator of Low-Density Lipoprotein Receptor, Enhances Follicular Development in Mouse Ovaries.

Ovarian aging hampers in vitro fertilization in assisted reproductive medicine and has no cure. Lipoprotein metabolism is associated with ovarian aging. It remains unclear how to overcome poor follicular development with aging. Upregulation of the low-density lipoprotein receptor (LDLR) enhances oogenesis and follicular development in mouse ovaries. This study investigated whether upregulation of LDLR expression using lovastatin enhances ovarian activity in mice. We performed superovulation using a hormone and used lovastatin to upregulate LDLR. We histologically analyzed the functional activity of lovastatin-treated ovaries and investigated gene and protein expression of follicular development markers, using RT-qPCR and Western blotting. Histological analysis showed that lovastatin significantly increased the numbers of antral follicles and ovulated oocytes per ovary. The in vitro maturation rate was 10% higher for lovastatin-treated ovaries than for control ovaries. Relative LDLR expression was 40% higher in lovastatin-treated ovaries than in control ovaries. Lovastatin significantly increased steroidogenesis in ovaries and promoted the expression of follicular development marker genes such as anti-Mullerian hormone, Oct3/4, Nanog, and Sox2. In conclusion, lovastatin enhanced ovarian activity throughout follicular development. Therefore, we suggest that upregulation of LDLR may help to improve follicular development in clinical settings. Modulation of lipoprotein metabolism can be used with assisted reproductive technologies to overcome ovarian aging.

Role of diacerein on steroidogenesis and folliculogenesis related genes in ovary of letrozole-induced PCOS mice

Polycystic ovary syndrome (PCOS), an intricate and multifaceted metabolic-endocrine disorder that typically affects 6–20% of women of reproductive age and accounts for 70–80% of all occurrences of infertility globally. In this study we focussed on the effect of diacerein (DIC) on steroidogenesis and follicle development in addition to the basic metabolic and endocrine problems which are associated with PCOS. Eighteen mature female parkes strain mice were separated into three groups at random with 6 animals in a group as follows: Group I, received water and normal diet for 66 days; group II received letrozole (LETZ) (6 mg/kg bw) for the induction of PCOS; Group III received LETZ (6 mg/kg) for 3 weeks followed by the administration of DIC (35 mg/kg) for 45 days. In our study we observed that mice with PCOS had irregular estrous cycle with increased LH/FSH, estrogen level and decline in expression of Kitl, Bmp, Cyp11a1, CYP19a1, Ar, lhr, Fshr and Esr1 as well as decreased SOD and CAT activity in ovary. Moreover, we observed increase in the expression of CYP17a1, as well as increase in serum cholesterol, triglycerides, testosterone, LH, VEGF and insulin levels. All these changes were reversed after the administration of DIC in PCOS mice. Diacerin administration reversed abnormalities in mice with PCOS by modulating the regulation of genes which are related to steroidogenesis and folliculogenesis.

Abstract 654: Ovarian cancer-cell glucocorticoid receptor activity modulates cytokine secretion promoting infiltration of immunosuppressive cells into the tumor microenvironment

Abstract Elevated levels of immunosuppressive myeloid-derived suppressor cells (MDSCs) circulate in the peripheral blood or infiltrate the tumors as well as ascites in ovarian cancer patients, however the cause for this observed phenotype is unknown. MDSCs contribute to tumor immune tolerance primarily via inhibition of cytotoxic T-cells or by activation of immunosuppressive T-regulatory cells. We previously showed that high tumor cell glucocorticoid receptor (GR) expression is associated with a relatively poor prognosis in ovarian cancer patients. Additionally, using primary tumor data retrieved from the ovarian cancer TCGA dataset, we show high tumor GR expression is associated with significantly higher expression of Foxp3, a marker of immunosuppressive T-regulatory cells, as well as CD33, a marker of immunosuppressive myeloid cells, further suggesting an immunosuppressive phenotype in ovarian cancer patients. We thus hypothesize that tumor-intrinsic GR activation in ovarian cancer is associated with increased MDSC infiltration into the tumor microenvironment in part via modulating tumor cell cytokine secretion. To determine whether tumor-cell GR activation modulates the cytokine secretome, we previously showed that GR activation in ovarian cancer cells upregulated secretion of immunomodulatory factors including G-CSF, TGFb and CXCL5. Moreover, co-treatment of cells with a selective GR modulator (SGRM), reverses this secretome effect. Considering that elevated levels of these cytokines are necessary for the production and recruitment of MDSCs, these data highlight the relevance of this evident glucocorticoid receptor-cytokine circuit in ovarian cancer tumor cells. Furthermore, we show that this tumor-cell cytokine secretome has the capacity to promote differentiation of MDSCs from precursor myeloid cells in healthy PBMCs. Importantly, measuring expression of activation markers such as Arginase-1 and NOS2 illustrated that these MDSCs are in their functional state. To our knowledge this is the first evidence that a nuclear receptor in ovarian cancer tumor cells is actively driving MDSC differentiation. Finally, employing ovarian cancer xenograft models as well as a syngeneic ID8 tumor model, treatment with SGRMs demonstrated reduced levels of circulating MDSCs in the peripheral blood as well as tumor infiltrated MDSCs. Using neutralizing antibodies for cytokines, we will now identify key mechanisms, specifically, identify which targetable immunomodulatory factors are contributing to immune suppression. Based on the insight provided by these data, we propose to determine whether targeting ovarian tumor cell-intrinsic GR activation and resulting MDSC infiltration contributes to improved anti-tumor immune response. Citation Format: Manisha Taya, Eleanore LeBlanc, Lynda Bennett, Suzanne D. Conzen. Ovarian cancer-cell glucocorticoid receptor activity modulates cytokine secretion promoting infiltration of immunosuppressive cells into the tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 654.

BORİK ASİT SIÇANLARDA SİKLOFOSFAMİDİN NEDEN OLDUĞU KARACİĞER HASARINI İYİLEŞTİRİR

Introduction: The aim of the current study was to look into any potential ameliorative benefits of boric acid on liver damage in rats caused by cyclophosphamide (CTX). &#x0D; Materials and Methods: Four groups; control, boric acid, CTX, and boric acid + CTX, were created. Female Wistar albino rats were given daily injections of CTX (75 mg/kg) to create the liver damage model. Cyclophosphamide (75 mg/kg) was administered intraperitoneally, and boron (1.3 g/rat/day) was administered by gavage every day for two weeks in the boric acid+CTX group. The histopathological changes were evaluated in ovarian tissue staining with hematoxylin and eosin, masson tricrom, and periodic acid Schiff. We assessed ovarian tissue enzyme activity as malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px). &#x0D; Results: Images in the boric acid+CTX group had lower histological evaluations than those in the CTX group under the light microscope. According to the findings, boric acid reduced the levels of malondialdehyde (MDA) in the liver tissues. Additionally, boric acid improved the actions of oxidative stress indicators to reduce oxidative stress brought on by CTX and upregulated antioxidant parameters.&#x0D; Conclusion: In conclusion, our study have demonstrated that CTX- induced liver injury can be alleviated by reducing the tissue MDA levels, increasing the liver’s SOD, GSH-Px, and CAT activities. In order to reduce the liver damage caused by CTX, boric acid may be administered as a dietary supplement or functional food.

The ovaries of transgender men indicate effects of high dose testosterone on the primordial and early growing follicle pool.

Androgens are essential in normal ovarian function and follicle health but hyperandrogenism, as seen in polycystic ovary syndrome, is associated with disordered follicle development. There are few data on the effect of long-term exposure to high levels of testosterone as found in transgender men receiving gender-affirming endocrine therapy. In this study, we investigate the effect of testosterone on the development, morphological health and DNA damage and repair capacity of human ovarian follicles in vivo and their survival in vitro. Whole ovaries were obtained from transgender men (mean age: 27.6 ± 1.7 years; range 20-34 years, n = 8) at oophorectomy taking pre-operative testosterone therapy. This was compared to cortical biopsies from age-matched healthy women obtained at caesarean section (mean age: 31.8±1.5 years; range= 25-35 years, n=8). Cortical tissues were dissected into fragments and either immediately fixed for histological analysis or cultured for 6 days and subsequently fixed. Follicle classification and morphological health were evaluated from histological sections stained with H&E and expression of γH2AX as a marker of DNA damage by IHC. In uncultured tissue, testosterone exposure was associated with reduced follicle growth activation, poor follicle health and increased DNA damage. After 6 days of culture, there was enhanced follicle activation compared to control with further deterioration in morphological health and increased DNA damage. These data indicate that high circulating concentrations of testosterone have effects on the primordial and small-growing follicles of the ovary. These results may have implications for transgender men receiving gender-affirming therapy prior to considering pregnancy or fertility preservation measures.

The effect of rifampin on serum etonogestrel concentrations and biomarkers of ovulation among contraceptive implant users: A pharmacokinetic and pharmacodynamic study

ObjectivesRifampin, a strong CYP3A inducer, is the gold standard for evaluating CYP3A-mediated drug-drug interactions. We aimed to evaluate the pharmacokinetic and pharmacodynamic effects of a short course (2 weeks) of rifampin on serum etonogestrel (ENG) concentrations and serologic measures of ovarian activity (endogenous estradiol [E2] and progesterone [P4]) among ENG implant users. Study designWe enrolled healthy females using ENG implants for 12 to 36 months. We measured baseline serum ENG concentrations using a validated liquid chromatography mass-spectrometry assay and baseline E2 and P4 concentrations using chemiluminescent immunoassays. After 2 weeks of rifampin 600 mg daily, we repeated ENG, E2, and P4 measurements. We compared pre- and post-rifampin serum measurements using paired Wilcoxon signed-rank tests. ResultsFifteen participants completed all study procedures. Participants’ median age was 28.2 years (range 21.8–34.1), median body-mass index was 25.2 kg/m2 (range 18.9–37.3), and median duration of implant use was 22 months (range 12–32). All participants experienced significant decreases from baseline ENG concentrations (median 164.0 pg/mL [range 94.4–265.0]) to post-rifampin measurements (median 47.8 pg/mL [range 24.7–82.8]) (p < 0.001). Serum E2 concentrations also significantly increased with rifampin exposure (median 73 pg/mL vs 202 pg/mL, p = 0.003); increases in serum P4 concentrations were not statistically significant (p = 0.19). Three participants (20%) experienced increased luteal activity, with one presumptively ovulating post-rifampin (P4 = 15.8 ng/mL). ConclusionsWith only short exposure to a strong CYP3A inducer, ENG implant users experienced clinically significant decreases in serum ENG concentrations that led to changes in biomarkers indicative of waning suppression of ovulation. ImplicationsEven a short, 2-week course of treatment with rifampin places etonogestrel contraceptive implant users at risk for decreased contraceptive efficacy. Clinicians should counsel patients using etonogestrel implants considering any duration of rifampin therapy on the need for backup nonhormonal contraception or the use of an intrauterine device to avoid unintended pregnancies.

Evaluation of ovarian reserve in young females with non-iatrogenic ovarian insufficiency to establish criteria for ovarian tissue cryopreservation

Research questionCan ovarian reserve parameters predict the outcome of ovarian tissue cryopreservation (OTCP) in patients ≤18 years with non-iatrogenic premature ovarian insufficiency (POI)? DesignRetrospective cohort analysis carried out in a single tertiary hospital between August 2010 and January 2020. Thirty-seven patients ≤18 years with non-iatrogenic POI (27 with Turner syndrome, six with POI of unknown aetiology, three with galactosemia and one with blepharophimosis, ptosis, epicanthus inversus syndrome) were included. Three parameters were used to evaluate ovarian reserve: anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH) and transabdominal antral follicle count. Fertility preservation (most commonly OTCP) was offered if ovarian reserve was diminished and one or more parameters was positive. Follicles were counted in ovarian samples obtained at the time of OTCP. ResultsOvarian reserve was diminished in 34 patients and 19 of them had one or more positive parameter. Fourteen (11 aged ≥12 years and 3 aged <12) underwent OTCP, one (14 years old) underwent ovarian stimulation and oocyte cryopreservation and four declined fertility preservation. Follicles were detected in 11 of 14 patients who underwent OTCP with one or more positive parameters (79%), and in all those (100%) who had two or three positive parameters. The median number of follicles was 27 (range 5–64) and 48 (range 21–75) in patients ≥12 years and those <12 years, respectively. ConclusionThis study shows that if OTCP is performed in patients with one or more positive parameters of ovarian activity, a 79% positive predictive value is achieved for the detection of follicles. The incorporation of this criterion for OTCP will minimize the risk of harvesting ovarian tissue with a low number of follicles.