Increased Serum Progesterone Levels Research Articles

Outcomes of Pioglitazone and Metformin on Anthropometric, Metabolic and Endocrine variables in POS

Aim: To evaluate the outcomes of Pioglita zone and Metformin on anthropometric, metabolic and endocrine variables in PCOS. Methods: This randomized controlled trial was executed at Pharmacology Department of Bahria University Medical and Dental College in collaboration with Mamji Hospital Karachi from September 2018 to March 2019. Eighty PCOS infertile patients as per Rotterdam 2003 criteria,aged 20-40 years were enrolled. They were divided into two groups of 40 patients each by using computer generated numbers. All patients had fasting insulin levels of >9 μU/mL, serum glucose levels ≥126 mg/dl and suffering from oligomenorrhoea or amenorrhoea. Group A received Tablet Pioglitazone 30 mg once daily and group B was given tablet Metformin 500 mg for three months along with lifestyle changes. Results: Sixty-one participants completed the study. Anthropometric variables included weight, BMI and W/H ratio. Metformin treated group reduced more weight and BMI as compared to Pioglitazone. Metabolic variables included glycaemic indices, lipid profile and hs-CRP estimation. Pioglitazone group improved glycaemic indices more compared to Metformin. Serum progesterone level was significantly increased in Pioglitazone group (5.20±1.18) than Metformin group. Pioglitazone produced more ovulation in comparison to Metformin. Hence it is proved that it is better option in those patients who are unable to tolerate Metformin and cannot continue treatment for infertility. Conclusion: Pioglitazone group produced highly significant increase in serum progesterone level indicating ovulation and improved insulin resistance than the metformin group. Keywords: Female infertility, ovulation induction, Metformin, Pioglitazone, polycystic ovarian syndrome

Evolution of serum progesterone levels in the very early luteal phase of stimulated IVF/ICSI cycles post hCG trigger: a proof of concept study.

Studies have suggested that controlled ovarian hyperstimulation adversely affects endometrial receptivity due to advanced endometrial maturation. This adverse effect is mainly attributed to supraphysiological levels of both estrogen and progesterone identified in stimulated cycles. There is a paucity of published data investigating the very early luteal steroid profile following hCG trigger. This prospective, observational study was undertaken to determine the increase in serum progesterone levels after human chorionic gonadotrophin (hCG) trigger in stimulated IVF/ICSI cycles. This proof-of-concept study included 11 patients requiring ovarian stimulation for IVF/ICSI and who planned to avail of pre-implantation genetic screening with embryo vitrification of their biopsied embryos at blastocyst stage. For each study participant, five additional blood samples were drawn at the following specific times in the stimulation cycle, on the morning (10.00-12.00) of the assigned day to induce final oocyte maturation with hCG trigger, immediately prior to administration of hCG for final oocyte maturation, 1h, 2h, and 36h post hCG trigger. A prediction model, the Gompertz curve, was used to determine serum progesterone levels at intervals between the 2h post hCG trigger sample and the day of oocyte retrieval. Statistically significant increases in serum progesterone levels were identified following hCG administration as early as 1h following trigger (P4 0.57ng/ml, p < 0.05), 2h following trigger (P4 0.88ng/ml, p < 0.001) and on the day of oocyte retrieval (P4 9.68ng/ml, p < 0.001). According to our prediction model, the Gompertz curve, the projected serum progesterone level at 4h post trigger would have achieved a level of 1.45ng/ml, 8h post trigger of 3.04ng/ml, and 12h post trigger of 4.8ng/ml. The very early and significant increases in serum progesterone following hCG trigger are clearly demonstrated in this study. The endometrium is undoubtedly exposed to rapidly increasing serum progesterone levels post hCG trigger that would not be identified until much later in natural menstrual cycles. This study is registered with clinicaltrials.gov under the identifier NCT04417569.

ASSOCIATION BETWEEN PROGESTERONE LEVEL ON HUMAN CHRONIC GONADOTROPIN (HCG) TRIGGER DAY AND CLINCAL OUTCOMES OF CLEAVAGE-STAGE EMBRYOS OR BLASTOCYSTS TRANSFER IN ASSISTED REPRODUCTION TECHNOLOGY (ART) CYCLES

Several studies have reported that increased progesterone levels, usually defined as greater than 1.5 ng/mL, occur on the human chronic gonadotropin (hCG) day in approximately 6-30% of COH cycles. The increased serum progesterone level on the day of hCG administration is associated with significantly lower ongoing pregnancy rates in in vitro fertilization and embryo transfer (IVF-ET) cycles. However, the effect of increased serum progesterone levels on the day of hCG administration in COH cycles on clinical outcomes for different embryos transfer remains controversial.

Expression of steroidogenic enzymes and TGFβ superfamily members in follicular cells of prepubertal gilts with distinct endocrine profiles.

Regulation of the transforming growth factor beta (TGFβ) superfamily by gonadotrophins in swine follicular cells is not fully understood. This study evaluated the expression of steroidogenic enzymes and members of the TGFβ superfamily in prepubertal gilts allocated to three treatments: 1200 IU eCG at D -3 (eCG); 1200 IU eCG at D -6 plus 500 IU hCG at D -3 (eCG + hCG); and the control, composed of untreated gilts. Blood samples and ovaries were collected at slaughter (D0) and follicular cells were recovered thereafter. Relative gene expression was determined by real-time PCR. Serum progesterone levels were greater in the eCG + hCG group compared with the other groups (P < 0.01). No differences were observed in the expression of BMP15, BMPR1A, BMPR2, FSHR, GDF9, LHCGR and TGFBR1 (P > 0.05). Gilts from the eCG group presented numerically greater mean expression of CYP11A1 mRNA than in the control group that approached statistical significance (P = 0.08) and greater expression of CYP19A1 than in both the eCG and the control groups (P < 0.05). Expression of BMPR1B was lower in the eCG + hCG treatment group compared with the control (P < 0.05). In conclusion, eCG treatment increased the relative expression of steroidogenic enzymes, whereas treatment with eCG + hCG increased serum progesterone levels. Although most of the evaluated TGFβ members were not regulated after gonadotrophin treatment, the downregulation of BMPR1B observed after treatment with eCG + hCG and suggests a role in luteinization regulation.

Effects of Resveratrol on Receptor Expression and Serum Levels of Estrogen and Progesterone in the Rat Endometritis Model.

Endometritis is characterized by inflammation of the endometrial lining that leads to reduced reproductive potential. Restoring the impaired hormonal balance is an important component of endometritis treatment. The purpose of the current study was to evaluate the effects of resveratrol on estrogen and progesterone hormone status in endometritis. Mature female Sprague Dawley rats were used, and endometritis was induced by intrauterine infusion of Escherichia coli. Animals were treated with resveratrol alone or combined with marbofloxacin. Compared to the non-treated endometritis group, resveratrol treatment reduced serum oestradiol levels, increased serum progesterone levels, enhanced estrogen receptor (ER) expression in the uterine stroma, decreased ESR1 gene expression, and raised ESR2 gene expression. Resveratrol administration combined with marbofloxacin also increased ER expression in the uterine gland and progesterone receptor expression in the uterine epithelium. The findings of this study suggest that the actions of resveratrol on progesterone levels and estrogen receptor expression might be responsible for its beneficial effect in rats with endometritis.

Progesterone impairs antigen-non-specific immune protection by CD8 T memory cells via interferon-γ gene hypermethylation.

Pregnant women and animals have increased susceptibility to a variety of intracellular pathogens including Listeria monocytogenes (LM), which has been associated with significantly increased level of sex hormones such as progesterone. CD8 T memory(Tm) cell-mediated antigen-non-specific IFN-γ responses are critically required in the host defense against LM. However, whether and how increased progesterone during pregnancy modulates CD8 Tm cell-mediated antigen-non-specific IFN-γ production and immune protection against LM remain poorly understood. Here we show in pregnant women that increased serum progesterone levels are associated with DNA hypermethylation of IFN-γ gene promoter region and decreased IFN-γ production in CD8 Tm cells upon antigen-non-specific stimulation ex vivo. Moreover, IFN-γ gene hypermethylation and significantly reduced IFN-γ production post LM infection in antigen-non-specific CD8 Tm cells are also observed in pregnant mice or progesterone treated non-pregnant female mice, which is a reversible phenotype following demethylation treatment. Importantly, antigen-non-specific CD8 Tm cells from progesterone treated mice have impaired anti-LM protection when adoptive transferred in either pregnant wild type mice or IFN-γ-deficient mice, and demethylation treatment rescues the adoptive protection of such CD8 Tm cells. These data demonstrate that increased progesterone impairs immune protective functions of antigen-non-specific CD8 Tm cells via inducing IFN-γ gene hypermethylation. Our findings thus provide insights into a new mechanism through which increased female sex hormone regulate CD8 Tm cell functions during pregnancy.

A Potential Role for Endoplasmic Reticulum Stress in Progesterone Deficiency in Obese Women.

Obesity in reproductive-aged women is associated with a shorter luteal phase and lower progesterone levels. Lipid accumulation in follicles of obese women compromises endoplasmic reticulum (ER) function, activating ER stress in granulosa cells. We hypothesized that ER stress activation in granulosa-lutein cells (GLCs) would modulate progesterone production and contribute to obesity-associated progesterone deficiency. Pretreatment with an ER stress inducer, tunicamycin or thapsigargin, inhibited human chorionic gonadotropin (hCG)-stimulated progesterone production in cultured human GLCs. Pretreatment of human GLCs with tunicamycin inhibited hCG-stimulated expression of steroidogenic acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) messenger RNAs (mRNAs) without affecting expression of cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), as determined by real-time quantitative polymerase chain reaction. Pretreatment with tunicamycin also inhibited hCG-stimulated expression of StAR protein and 3β-HSD enzyme activity in cultured human GLCs, as determined by Western blot analysis and an enzyme immunoassay, respectively, but did not affect hCG-induced intracellular 3',5'-cyclic adenosine monophosphate accumulation. Furthermore, tunicamycin attenuated hCG-induced protein kinase A and extracellular signal-regulated kinase activation, as determined by Western blot analysis. In vivo administration of tunicamycin to pregnant mare serum gonadotropin-treated immature mice prior to hCG treatment inhibited the hCG-stimulated increase in serum progesterone levels and hCG-induced expression of StAR and 3β-HSD mRNA in the ovary without affecting serum estradiol levels or the number of corpora lutea. Our findings indicate that ER stress in the follicles of obese women contributes to progesterone deficiency by inhibiting hCG-induced progesterone production in granulosa cells.

Activation of Peroxisome Proliferator-activated Receptor γ (PPARγ) and CD36 Protein Expression: THE DUAL PATHOPHYSIOLOGICAL ROLES OF PROGESTERONE

Progesterone or its analog, one of components of hormone replacement therapy, may attenuate the cardioprotective effects of estrogen. However, the underlying mechanisms have not been fully elucidated. Expression of CD36, a receptor for oxidized LDL (oxLDL) that enhances macrophage/foam cell formation, is activated by the transcription factor peroxisome proliferator-activated receptor γ (PPARγ). CD36 also functions as a fatty acid transporter to influence fatty acid metabolism and the pathophysiological status of several diseases. In this study, we determined that progesterone induced macrophage CD36 expression, which is related to progesterone receptor (PR) activity. Progesterone enhanced cellular oxLDL uptake in a CD36-dependent manner. Mechanistically, progesterone increased PPARγ expression and PPARγ promoter activity in a PR-dependent manner and the binding of PR with the progesterone response element in the PPARγ promoter. Specific deletion of macrophage PPARγ (MφPPARγ KO) expression in mice abolished progesterone-induced macrophage CD36 expression and cellular oxLDL accumulation. We also determined that, associated with gestation and increased serum progesterone levels, CD36 and PPARγ expression in mouse adipose tissue, skeletal muscle, and peritoneal macrophages were substantially activated. Taken together, our study demonstrates that progesterone can play dual pathophysiological roles by activating PPARγ expression, in which progesterone increases macrophage CD36 expression and oxLDL accumulation, a negative effect on atherosclerosis, and enhances the PPARγ-CD36 pathway in adipose tissue and skeletal muscle, a protective effect on pregnancy.

Effect of premature serum progesterone rise on embryo transfer outcomes and the role of blastocyst culture and transfer in assisted reproductive technology cycles with premature progesterone rise

ObjectiveIn 1991, researchers reported that a modest preovulatory increase in serum progesterone levels is associated with lower pregnancy rates and higher incidence of pregnancy loss in in vitro fertilization (IVF). We wonder whether embryo transfer (ET) in assisted reproductive technology (ART) cycles in patients with premature progesterone rise (PPR) have a negative impact on the clinical pregnancy rates (CPRs) and/or live birth rates (LBRs) in our series. Consequently, will blastocyst transfer reverse the negative impact? Materials and methodsThis noninterventional, retrospective, observational tertiary center study was conducted between January 2010 and December 2012. All fresh ET cycles with serum progesterone levels measured (n = 599) on the day of hCG administration were analyzed. ResultsSera lutenizing hormone (LH), E2, and progesterone (P) were measured and analyzed. The CPRs of cycles in patients with p ≤ 1.5 ng/mL (low) versus those with p > 1.5 ng/mL (high) were 37.04% versus 41.03% [odds ratio (OR) = 1.18, 95% confidence interval (CI): 0.728–1.920; p = 0.50). The LBRs of cycles in patients with low progesterone level versus those with PPR were 30.52% versus 34.62% (OR = 1.21, 95% CI: 0.729–1.992; p = 0.47). No statistically significant association was detected. We further analyzed the outcomes according to different stages of ET and found that blastocyst (D5) ET significantly increase the LBRs as compared with cleavage stage (D2/D3) ET in the PPR group (44.44% versus 21.43%; p = 0.043). ConclusionPPR did not significantly compromise the clinical outcomes in this series. However, shifting to blastocyst transfer probably could increase the live birth in cycles with PPR.

Late pregnancy progesterone treatment as a modulatory signal for postpartum behavior

Changes in plasma progesterone levels during late pregnancy are a determining factor in the expression of maternal behavior during lactation. Previous studies showed that mild opioidergic stimulation during late pregnancy makes lactating females more sensitive to opioidergic-induced inhibition of maternal behavior and more willing to display hunting behavior. Such previous behaviorally meaningful opioidergic stimulation also selectively increased serum progesterone levels. The present study tested whether progesterone treatment during late pregnancy interferes with the display of maternal behavior and behavioral selection during lactation. In Experiment 1, rats were treated with progesterone (400 and 500μg per day) from the 17th day to the 22nd day of pregnancy. The lowest progesterone dose did not interfere with pregnancy or parturition, and this dose was used in Experiments 2 and 3, in which the rats were treated with subcutaneous progesterone or peanut oil for 5days beginning on pregnancy day 17. On day 5 of lactation, dams were challenged with subcutaneous morphine (1.5mg/kg), or saline. The rats were then tested for maternal care (Experiment 2) or behavioral selection with pups and cockroaches (Experiment 3). Animals treated with progesterone during late pregnancy and challenged with morphine during lactation exhibited a significant decrease in maternal behavior in both Experiments 2 and 3. Predatory hunting was not modified by progesterone treatment. These results indicate that sensitivity to opioidergic-mediated inhibition of maternal behavior is enhanced by prepartum progesterone administration. Thus progesterone might be part of the opioid-triggered prepartum signaling leading to behavioral changes during lactation.

Passage of Decidual Cast Following Poor Compliance with Oral Contraceptive Pill

Background: Decidual cast describes the spontaneous sloughing of endometrium as an entire piece while retaining the shape of the endometrial cavity. It may be associated with increased serum progesterone levels and must be considered as a differential diagnosis in a patient who passes tissue per vagina while on progesterone containing hormonal contraception. Case: A 13-year-old adolescent with a history of menorrhagia since menarche, presented to the pediatric emergency room with worsening abdominal pain and heavy vaginal bleeding stopping her oral contraceptive pill 10 days prior to presentation. Her symptoms resolved spontaneously following passage of tissue per vagina which was later by histopathology to be a decidual cast. Conclusion: Decidual cast is a rare pathological entity that may be a side effect of progesterone-containing hormonal contraceptives, requiring patient education before use.

Involvement of progesterone receptors in ascorbic acid–mediated protection against ischemia-reperfusion–induced acute kidney injury

BackgroundAscorbic acid (AA) is an established antioxidant and has been used for treatment of various disorders. Recent reports suggest that administration of AA increases the level of steroids such as progesterone in the body. The present study investigated the protective role of progesterone against ischemia-reperfusion–induced acute kidney injury (AKI) and possible involvement of progesterone receptors in AA-mediated renoprotection in rats. Materials and methodsThe male rats were subjected to bilateral renal ischemia for 40 min followed by reperfusion for 24 h to induce AKI. The rats were treated with progesterone (5 and 10 mg/kg, intraperitoneally) and AA (500 mg/kg, intraperitoneally for 1, 2, and 5 d) before AKI. In separate groups, mifepristone, the progesterone receptor antagonist was administered to rats before progesterone (10 mg/kg) and AA treatment (5 d). Various parameters including creatinine clearance, serum urea, uric acid, potassium level, fractional excretion of sodium, lactate dehydrogenase, and microproteinuria were used to assess kidney injury. Moreover, renal tissues were subjected to quantification of oxidative stress and evaluation of histopathologic changes. ResultsThe exogenous administration of progesterone afforded protection against AKI in a dose-dependent manner that was abolished by mifepristone. The administration of AA for 1, 2, and 5 d induced significant increase in serum progesterone levels and afforded protection against AKI. The antioxidant and renoprotective effect of AA was abolished by prior treatment with mifepristone. ConclusionsIt is concluded that exogenous administration of progesterone exerts significant antioxidant and renoprotective effect. Moreover, the progesterone receptors find their explicit involvement in AA-mediated renoprotection against ischemia-reperfusion–induced AKI in rats.

Effect of copper intrauterine device vs. injectable contraceptive on serum hormone levels and cell mitotic activity in endometrium

Abstract Aims To compare changes in serum estradiol and progesterone level, endometrium cell mitotic activity and Ki67 in women using copper intrauterine device (Cu-IUD) with DMPA users 9 months after use. Methods One hundred and fifty women having no contra indication to either IUD or injectable contraceptive were studied. Office Endometrial biopsies and serum samples for estradiol and progesterone levels were taken on the 7th day of the menstrual cycle at recruitment and after 9 months. The endometrial samples were subjected to cell mitotic study and Ki67 estimation using morphology and proliferative indices. Results The mean glandular mitotic index was 1.69 ± (0.39) for IUD user vs. 1.1 ± (0.69) for Injectable contraceptive user at first visit respectively and it was 0.57 ± (0.34) vs. 0.25 ± (0.11) at second visit after 9 months respectively. Similarly, Ki-67 count in glands was 11.79 ± 1.59 for IUD user vs. 12.03 ± 0.58 for injectable contraceptive user at first visit and 4.20 ± (0.24) vs. 2.27 ± (0.65) at second visit respectively. In the stroma, Ki67 decreased from a mean of 0.85–0.05 in 9 months for IUD user vs. 0.92–0.02. For injectable users suggesting a statistically significant decrease in proliferative and mitotic indices in the endometrium of women using either injectable contraceptives or IUD for more than 9 months. Non significant changes were observed in serum hormone levels in IUD users, while injectable contraceptive users showed a significant increase in serum progesterone level with insignificant change in the serum estrogen level. Conclusion Either copper intrauterine device or injectable contraceptive usage for more than 9 months results in significant decrease in endometrial proliferative or cell mitotic activity. While copper IUD has no effect on serum estradiol or progesterone levels, DMPA usage increased serum progesterone level with no effect on serum estradiol.

Individualized High-Dose Cabergoline Therapy for Hyperprolactinemic Infertility in Women With Micro- and Macroprolactinomas

The dopamine receptor agonist, bromocriptine, has been first-line treatment for hyperprolactinemic infertility in young women of reproductive age with pituitary hormone-producing adenomas for the past 30 years. Several studies have shown that cabergoline has superior efficacy and tolerability, and in recent years, it has replaced bromocriptine as the first-choice dopamine agonist in this population. In women with hyperprolactinemic amenorrhea, cabergoline corrects hyperprolactinemia and is more effective than bromocriptine in achieving recovery of the ovulatory cycle. Although cabergoline can induce pregnancy in prolactinoma patients, the rate of pregnancy induction in these women is unknown. In patients with macroprolactinomas (macroadenomas), its effectiveness for controlling tumor growth and thereby inducing successful pregnancy is also unknown. The aim of this study was to determine the efficacy and safety of cabergoline in pregnancy induction and its outcomes in infertile women with prolactinomas. Between 2001 and 2005, the participants—85 infertile women with macroprolactinomas (n = 29) or microprolactinomas (n = 56)—received prospective, high-dose cabergoline therapy for suppression of prolactin and tumor shrinkage. Of the 85 subjects, 31 were bromocriptine resistant, 32 were bromocriptine intolerant, and 22 were newly diagnosed untreated patients. Conception was withheld in patients with microadenomas or macroadenomas until 3 regular menstrual cycles returned and in women with macroadenomas until tumors shrunk to less than 1 cm in height. The drug was withdrawn at the fourth gestational week. Cabergoline corrected and normalized hyperprolactinemia, increased serum progesterone levels and achieved recovery of the ovulatory cycle in all patients. Within 6 to 24 months after the initiation of cabergoline therapy, all tumors contracted, and 11 of the 29 macroadenomas and 29 of the 56 microadenomas disappeared. Of the 85 patients, 80 (94%) conceived 95 pregnancies; 2 of the 95 were second pregnancies conceived without use of cabergoline. The drug dose at the first pregnancy varied widely (0.25-9 mg/week overall and 2-9 mg/week in bromocriptine-resistant patients). Of the 93 pregnancies induced with cabergoline, 86 resulted in 83 single live births, 1 stillbirth, and 2 abortions (1 of which was spontaneous); the remaining 7 pregnancies were ongoing. All newborns were healthy, without malformations or abnormal development. None of the mothers experienced impaired vision or headache suggestive of abnormal macroprolactinoma re-expansion during pregnancy. These findings show that cabergoline can safely induce and promote successful pregnancy in most infertile women with prolactinoma, independent of tumor size or bromocriptine resistance and intolerance. Cabergoline monotherapy has the potential to substitute for the conventional combination therapy of surgery or radiotherapy plus bromocriptine in patients with macroadenomas.

Glucose can reverse the effects of acute fasting on mouse ovulation and oocyte maturation

Food deprivation suppresses ovulation. Although nutritional elements are responsible for this suppression, it is not clear whether energy metabolism has any effect on oocyte development under these circumstances. The aim of the present study was to determine which nutritional element is responsible for the effect of acute fasting on mouse ovulation and how oocyte development is affected. The results demonstrate that 64 h food deprivation blocks mouse ovulation. This was reversed by glucose feeding, oil feeding or short-term feeding, all of which elevated serum glucose levels. Furthermore, 48 h food deprivation inhibited follicle-stimulating hormone-induced oocyte maturation in vitro. However, 48 h glucose feeding increased serum glucose levels and restored oocyte maturation. Food deprivation increased serum progesterone levels and decreased serum oestradiol levels. Food deprivation also impaired follicle development, caused the death of oocytes and attenuated glucose consumption by cumulus-oocyte complexes. Taken together, the results indicate that: (1) the suppression of ovulation by acute fasting may be due to the control of oocyte development; and (2) maintaining serum glucose concentrations at a certain level is important for normal ovulation.

Effects of CDB-4022 on Leydig Cell Function in Adult Male Rats1

CDB-4022, an indenopryridine, suppresses spermatogenesis and decreases inhibin secretion in adult male rats. In the present study, we investigated the effects of CDB-4022 on Leydig cell function. A single oral dose of CDB-4022 (2.5 mg/kg) resulted in a 2-fold decrease in serum testosterone levels after 7 days that was paralleled by a decrease in Cyp17a1 mRNA and protein levels and 17alpha hydroxylase enzymatic activity compared with vehicle-treated rats. Consistent with the lower serum testosterone levels, pituitary Lhb and Fshb mRNA levels were increased 3.2- and 2.3-fold, respectively, by CDB-4022 treatment. Ultrastructural analysis of pituitary gonadotrophs showed distended endoplasmic reticulum (ER) and fewer secretory granules in CDB-4022-treated rats, characteristic of enhanced secretory activity. Conversely, CDB-4022 increased serum progesterone levels, testicular Star mRNA and protein expression, and the number of Leydig cells per testis. Serum inhibin B levels were undetectable in CDB-4022-treated rats, while serum activin A levels were similar to controls, indicating that the CDB-4022-treated rats have an elevated activin A:inhibin B ratio. In the presence of hCG stimulation, activin A directly suppressed testosterone secretion but enhanced progesterone secretion from rat Leydig cell primary cultures. Likewise, treatment of MA-10 cells with activin A was found to enhance cAMP-stimulated progesterone secretion and STAR expression. Together, our data indicate that CDB-4022 treatment inhibits CYP17A1 and stimulates STAR expression, thereby decreasing testosterone but increasing progesterone production. We propose that unopposed actions of activin A most likely contribute to the steroid profile in rats after CDB-4022 treatment. Our findings establish CDB-4022 as a new model to examine intratesticular control mechanisms that modulate Leydig cell gene expression and function.

Prolonged Increase in T-Cell Receptor (TCR) Variant Fractions of Spleen T Lymphocytes in Pregnant Mice after γ Irradiation

To investigate the relationship between the radiation-induced increase of T-cell receptor (TCR) defective variant fractions and physiological status such as pregnancy, C57BL/ 6N mice were irradiated with 3 Gy of gamma rays at various days of gestation, just before and just after pregnancy. While the highest level of variant fractions in spleen T lymphocytes appeared at 9 days postirradiation and resolved fairly rapidly for nonpregnant mice, the increased variant fractions for pregnant mice irradiated at 16.5 days of gestation reached a plateau at 14 days postirradiation and remained at high levels until 28 days after irradiation. Therefore, variant fractions 28 days postirradiation were measured to determine the overall effect of radiation on the kinetics of TCR variant fractions during gestation. There was no significant difference in the baseline TCR variant fraction between unirradiated nonpregnant and pregnant mice. TCR variant fractions after irradiation were about twofold higher in pregnant mice (from 10.5 days of gestation until delivery) than those in nonpregnant mice. Both gamma radiation and pregnancy caused a decrease in the proportion of naïve T-cell subsets and an increase in TCR variant fractions of naïve T cells. In addition, the prolonged postirradiation increase in the TCR variant fractions of pregnant mice was associated with an increase in serum progesterone level. Differences between pregnant and nonpregnant mice in the kinetics of postirradiation restoration of T-cell systems may be involved in producing the differences in residual TCR variant fractions of these mice.

Progesterone and environmental tobacco smoke act synergistically to exacerbate the development of allergic asthma in a mouse model

Asthma affects males and females differently. Females have a higher incidence than males after the onset of puberty. This suggests a hormonal component to the development of the disease. Progesterone, a female hormone, has previously been shown to illicit a T-helper type 2 (TH2) immune response similar to that seen in allergic asthma. Previous studies performed by our laboratory have shown that exposure to environmental tobacco smoke (ETS) enhances the immune response to allergens. To determine if the combination of exposure to ETS and progesterone would further exacerbate the immune response in a mouse model of allergic asthma. Female mice were ovariectomized and then implanted with time-release progesterone pellets. Mice were housed in either filtered air (FA) or ETS chambers and half were exposed to aerosolized house dust mite allergen (HDMA). Bronchoalveolar lavage was performed for cell differentials; lung and spleen cells were harvested to compare IL-4 and IFN-gamma production by ELISPOT. Progesterone pellet implantation resulted in increased serum progesterone levels (28.3+/-8.43 vs. 13.5+/-7.22 ng/mL in placebo-treated mice, P<0.0001). Serum total IgE levels were significantly greater in progesterone vs. non-progesterone treated animals that were also exposed to HDMA. ETS exposure enhanced total IgE levels as well. Lung homogenate cells from HDMA/progesterone-treated animals stimulated with Concavalin A produced significantly more IL-4 compared with HDMA/placebo-treated animals (200+/-17.6 vs. 146+/-17.5 spots/well, P<0.01 in ETS exposed animals and 221+/-28.9 vs. 167+/-23.4 spots/well, P<0.01 in animals housed in FA). HDMA/ETS-treated animals had higher eosinophilia in lavage than all other groups. Increased serum progesterone levels exacerbate the allergic asthmatic phenotype in a mouse model. These effects are further exacerbated by the addition of environmental tobacco smoke. Progesterone provides a major contribution to the gender differences seen in the development and elicitation of the asthmatic response.

Single Injections of Vascular Endothelial Growth Factor Trap Block Ovulation in the Macaque and Produce a Prolonged, Dose-Related Suppression of Ovarian Function

The development of ovarian follicles is accompanied by marked angiogenesis and increased permeability of blood vessels. These changes are regulated by locally produced angiogenic factors, including vascular endothelial growth factor (VEGF). Experiments to date have inhibited the VEGF pathway using antibodies directed against VEGF itself. The investigators have used a very potent receptor-based VEGF antagonist, VEGF Trap A 4 0 , for the same purpose. This study examined the effects of transiently inhibiting VEGF on pituitary-ovarian function in macaques. Test animals received a single intravenous injection of VEGF Trap in doses of 0.25 to 4 mg/kg in the midfollicular phase or 1 mg/kg in the late follicular phase. Control animals received either vehicle or a control protein, recombinant human Fc. A total of 13 adult female macaques were used in the study. Treatment with VEGF Trap A 4 0 in the midfollicular phase inhibited the expected late follicular increase in plasma estradiol and also led to a rapid fall in estradiol concentrations to levels expected in the early follicular phase. Plasma gonadotropin levels increased progressively within 2 to 3 days after injection, and the ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) increased in all animals (Fig. 1). After treatment, estradiol levels were significantly lower in VEGE Trap-treated cycles than in control cycles (Fig. 2). Levels of inhibin G also decreased after injection of VEGF Trap. Ovulation and formation of a functional corpus luteum failed to occur when expected, as indicated by increased serum progesterone levels. Ovarian activity returned to normal when plasma levels of unbound VEGF Trap had decreased to approximately 1 mg/L. Both suppression of ovarian function and the delay in ovulation induced by VEGF Trap were dose-dependent. Posttreatment hormonal profiles were normal after ovarian function recovered. These findings indicate that VEGF Trap can aid the development of new treatments for some forms of ovarian dysfunction and infertility. This is particularly the case for conditions associated with pathologic angiogenesis and excessive vascular permeability such as polycystic ovary syndrome, ovarian hyperstimulation syndrome, and endometriosis.

Single Injections of Vascular Endothelial Growth Factor Trap Block Ovulation in the Macaque and Produce a Prolonged, Dose-Related Suppression of Ovarian Function

Follicular development is associated with intense angiogenesis and increased permeability of blood vessels under the control of locally produced angiogenic factors such as vascular endothelial growth factor (VEGF). The aim of the present study was to evaluate the effects of transient inhibition of VEGF on pituitary-ovarian function in the macaque. Animals were given a single, iv injection of a potent, receptor-based VEGF antagonist, the VEGF Trap. VEGF Trap was given at a dose of 4, 1, or 0.25 mg/kg in the midfollicular phase or at 1.0 mg/kg in the late follicular phase. Controls were treated with vehicle or a control protein, recombinant human Fc (1 mg/kg). Blood samples were collected once daily for 12 d after injection, and three times per week thereafter until normal ovulatory cycles had resumed. The VEGF Trap produced a rapid suppression of estradiol and inhibin B concentrations at all doses tested, followed by a marked and sustained increase in LH and FSH. Ovulation and formation of a functional corpus luteum, as evidenced by increased serum progesterone levels, failed to occur at the anticipated time. Normal ovarian activity resumed when plasma concentrations of unbound VEGF Trap fell below about 1 mg/liter. When treatment was initiated in the midfollicular phase, control macaques ovulated 7.2 +/- 0.4 d later, but ovulation was delayed in a dose-dependent manner by VEGF Trap, occurring 23 +/- 0.7, 30 +/- 1.4, and 43 +/- 0.8 d after injection of 0.25, 1, or 4 mg/kg, respectively. Thus, the VEGF Trap exerts a potent, dose-dependent, but reversible inhibitory effect on ovarian function.