THE EFFECTS OF ENDOCRINE DISRUPTORS ON FEMALE GONADAL AXIS: AN UPDATE.

Endocrine disruptors (EDs) are considered to have an impact on the function of reproductive axis at different levels as well on reproductive organs in both sexes. Complexity of female reproductive system influenced with various stressors including EDs lead to morphological and functional alterations. This is resulting in modulation of neuroendocrine regulation with consequent developmental irregularities and derangements, causative infertility, endometriosis as well as premature ovarian insufficiency or polycystic ovary syndrome. A number of experimental clues was obtained on female animal models using various EDs such as synthetic estrogens and phytoestrogens, neurotransmitters, pesticides or various chemicals. These substances lead towards consequent derangement of the neuroendocrine control of reproduction from early phases of reproductive development towards different phases of adult reproductive period. This text will address some novel insights into the effects of EDs on neuroendocrine regulation of gonadal axis, effects on ovaries as well on endometrium during implantation period.

The effect of metformin and myoinositol on metabolic outcomes in women with polycystic ovary syndrome: role of body mass and adiponectin in a randomized controlled trial.

PURPOSE: To compare the effects of insulin sensitizers metformin (MET) and myo-inositol (MI) on adiponectin levels and metabolic characteristics in women with polycystic ovary syndrome (PCOS) with respect to their body mass index (BMI). METHODS: In this open label, parallel randomized clinical trial, 66 women with PCOS (33 normal-weight and 33 overweight/obese) were randomized to either MI (4 g/day) or MET (1500 mg/day) for a period of 6 months. Serum concentration of adiponectin, hormonal and metabolic laboratory outcomes and clinical assessment of BMI, body composition and Ferriman-Gallwey score (FG score) were evaluated before and after treatment. RESULTS: After the 6-month intervention, comparison between MET and MI in time to treatment analysis showed no significant differences between the two treatments for all analyzed parameters. Only borderline significantly lower AUC glucose was found in the MET group in comparison to the MI group (p = 0.071). The main effect of treatment was shown for glucose concentration at 120 min OGTT (p = 0.032) and testosterone (p = 0.002). The main effect of time was shown for body mass (p = 0.004), waist circumference (p < 0.001), BMI (p = 0.003), body fat mass (p = 0.001), adiponectin (p = 0.020), fasting glucose (p = 0.001), testosterone (p = 0.015), SHBG (p = 0.013), 17OH progesterone (p = 0.008), LH (p = 0.004) and estradiol (p = 0.014). CONCLUSION: Our study showed similar effects of MET and MI on BMI, body composition, hormonal profile, metabolism of glucose and insulin, and adiponectin level. The two insulin sensitizers, MET and MI, were useful in reducing BMI and improving body composition without significant differences between the two treatments in PCOS women. TRIAL REGISTRATION: ISRCTN13199265. Trial registration date: 14.04.2021. (ISRCTN Registry), retrospectively registered.

EFFECT OF ORAL CONTRACEPTIVES ON BONE MINERAL DENSITY.

Contraceptives are widely used in our times and a lot of research has been conducted to clarify their impact on Bone Mineral Density. Combined Oral Contraceptives (COCs) may be detrimental to the BMD of adolescents. However, low-dose are more protective than ultra-low-dose COCs. When it comes to premenopause and perimenopause, COCs have no impact on BMD in women with good ovarian function and no estrogen deficiency. In women with impaired ovarian function, it seems that COCs have a positive influence on BMD. Progestin only-pills may not affect BMD, but further research is needed. Depot medroxyprogesterone acetate injection (DMPA) has a negative impact, especially in adolescents, which is duration related but evidence shows that BMD recovers after discontinuation. Levonorgestrel-releasing intrauterine system (LNG-IUS) has no impact on BMD.

Progestins and the Risk of Breast Cancer.

OBJECTIVES: The present paper aims to investigate the effects of both progesterone and progestin treatment mainly related to the occurrence of breast cancer in women. MATERIALS AND METHODS: Extensive systematic bibliographic review of Greek and International articles was conducted through the electronic databases Pubmed, Cinahl, Uptodate, and Google Scholar for the identification of articles related to progesterone, progestins and breast cancer treatment. RESULTS: Hormone therapy with the use of estrogen alone presents a small increased risk or does not present at all an increased risk of breast cancer. With ORs in some studies below 1.0 in current users for 3 plus years and safe option until 7 years, while in other studies the risk was increased with the ORs 1.29. However, the use of estrogen in combination with progestogens, depending on the type of progestogens, shows an increased risk of breast cancer, with the ORs to vary between 1.14- 2.38 from 3 to 5 years and is inversely proportional to the time of its use. This risk varies depending on the combination of the preparations. Other factors that are associated with breast cancer risk when receiving hormone therapy are the years that hormone therapy is taken, directly proportional to the risk. At higher risk are older women, women with low body mass index in menopause (BMI <25kg/m2) and women with increased mammographic breast density. Continued use of hormone therapy is associated with an increased risk for breast cancer compared to sequential. The risk became visible sooner to women who used in the past hormone therapy and were using it again. Starting hormone therapy in the immediate postmenopausal period also increased the risk for breast cancer. Hormone therapy was associated with tumors with positive estrogen and progesterone receptors, and also the lobular histological type was associated with its use. Tibolone use was associated with an increased risk.

THE EFFECT OF MYOINOSITOL AND METFORMIN ON CARDIOVASCULAR RISK FACTORS IN WOMEN WITH POLYCYSTIC OVARY SYNDROME: A RANDOMIZED CONTROLLED TRIAL.

CONTEXT: Cardiovascular risk is increased in women with polycystic ovary syndrome (PCOS). Do insulin sensitizing agents such as metformin (MET) and myoinositol (MI) ameliorate biomarkers of cardiovascular risk? OBJECTIVE: To compare the effects of MET and MI on blood pressure, lipid profile and high sensitive C-reactive protein (hs-CRP) in women with PCOS in respect to their body mass index (BMI). DESIGN: Open label, parallel randomized, single center study. SUBJECTS AND METHODS: Sixty six women with PCOS (33 normal-weight and 33 overweight/obese) were randomized to either MI (4 g/day) or MET (1500 mg/day) for a period of 6 months. Serum concentration of hormones, lipid profile, oxidized LDL (ox-LDL), hs-CRP, blood pressure measurement and clinical assessment of BMI, waist circumference (WC) and Ferriman Gallwey score (FG score) were performed before and after treatment. RESULTS: Thirty patients in each group completed the trial. Compared with MET, MI significantly decreased diastolic blood pressure (DBP) (p=0.036) and significantly increased serum hs-CRP (p=0.043). No differences between groups in total cholesterol (TC), HDL-cholesterol, LDL-cholesterol, ox-LDL and triglycerides were reported after 6 months. Treatment with MI reduced BMI (p=0.037), WC (p=0.005), DBP (p=0.021) and TC (p=0.008). During MET treatment a significant decrease in BMI (p=0.005), WC (p=0.004), FG score (p=0.001), testosterone (p=0.013) and free androgen index (FAI) (p=0.006) was observed. CONCLUSIONS: Our study showed an advantage of MI in reduction of DBP and TC thus predicting favorable metabolic and cardiovascular outcomes in PCOS women. MET more effectively decrease indices of hyperandrogenism.

ANTIMÜLLERIAN HORMONE AS INDICATOR OF OVARIAN DYSFUNCTION.

AIM: The purpose of this study was to examine various hormonal, biochemical and environmental factors (i.e., smoking and alcohol intake) and to investigate their possible correlation to the development of polycystic ovary syndrome (PCOS). The main objective was to evaluate the associations between hormonal profile and the antimüllerian hormone (AMH) levels in PCOS patients and their relation to environmental factors. PATIENTS AND METHODS: In two gynecological clinics, 38 women with PCOS (defined according to the Rotterdam criteria) were enrolled and observed in relation to AMH, follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), Δ4-androstendione (Δ4-A), dehydroepiandrosterone sulfate (DHEA-S) and glucose plasma concentrations. Obesity, smoking and alcohol exposure were also studied. RESULTS: AMH, T, Δ4-Α, DHEA-S, LH and FSH were increased in 76.3%, 50%, 31.8%, 23.7%, 21% and 18.4% of the patients, respectively. The LH/FSH ratio and glucose concentrations increased abnormally in 18.4% and 15.8% of the patients, respectively. AMH and T levels were both increased in 47.4% of the patients whereas both AMH and LH levels increased in 21% of the patients. Smoking, alcohol intake, obesity and glucose concentrations were not associated with AMH concentrations. On the contrary, high levels of T and LH were linked to higher levels of AMH. FSH concentrations were not increased in these patients. CONCLUSION: AMH is an important hormonal parameter for the diagnosis of PCOS. Larger clinical controlled studies are necessary in an effort to further investigate the inclusion of AMH measurement in the diagnostic criteria of PCOS.

Efficiency of GnRH analogues in treating large functional ovarian cysts.

AIM: The aim of this study was to determine the potential therapeutic benefit of a single administration of a GnRH analogue in pre- menopausal women presenting large functional ovarian cysts (FOCs) (diameter > five cm). MATERIALS AND METHODS: Fifty-one patients (median age 37.4 years) diagnosed with ovarian cysts, presumed benign based on transvaginal and/or transabdominal ultrasound, were divided in three study groups. Patients of group A received no medication whereas patients of groups B and C were treated with a single administration of a GnRH analogue and combined oral contraceptives, respectively. Patients were re-examined after a three-month period. Three of the 51 patients were lost in follow-up or stopped the treatment. RESULTS: Complete resolution of the ovarian cysts was observed in eight (50%), 14 (70%), and eight (67%) patients of groups A, B, and C, respectively. No side effects were observed in either of the three groups. The positive therapeutic effect in group B did not reach statistical significance compared with the two other groups (p > 0.05). CONCLUSION: Anew option of treating large FOCS through a single-dose of a GnRH analogue is proposed and should be carefully considered. Further research is needed in order to evaluate GnRH analogues as an alternative treatment.

Gender, age, puberty, and BMI related changes of TSH and thyroid hormones in schoolchildren living in a long-standing iodine replete area.

The aim of the work was to assess thyroid function in children and adolescents in an iodine replete area and to explore possible effects of age, gender, puberty, and adiposity. Thyrotropin (TSH), total triiodothyronine (T (3)), total thyroxine (T (4)), free thyroxine (FT (4)), and the T (4)/T (3) ratio were determined for 440 schoolchildren (200 boys and 240 girls), aged 5-18 years, living in an iodine replete region. Body Mass Index (BMI), BMI standard deviation score (BMI-SDS), and Body Surface Area (BSA) were calculated. In girls there was a negative correlation of TSH, T (3), and FT (4) values with age. In boys there was a negative correlation only of T (3) values with age. Girls had lower TSH, T (4), and T (3) values, whereas boys had only lower T (3) values at puberty compared to the prepubertal stage. Girls had lower TSH values than boys (p<0.03) only at puberty. BMI-SDS in boys and girls were 0.21 and 0.03, respectively. BMI-SDS was not related to TSH, T (4), or T (3) in either gender, whereas it was negatively related to T (4)/T (3) ratio in boys and to FT (4) in girls. We conclude that estrogens may exert a suppressive effect on the pituitary-thyroid axis after puberty. TSH values are not correlated with BMI-SDS, whereas T (4)/T (3) ratio in boys and FT (4) in girls are negatively correlated with BMI-SDS.

Peptide hormone analysis in diagnosis and treatment of Differences of Sex Development: joint position paper of EU COST Action 'DSDnet' and European Reference Network on Rare Endocrine Conditions.

Differences of Sex Development (DSD) comprise a variety of congenital conditions characterized by atypical chromosomal, gonadal, or anatomical sex. Diagnosis and monitoring of treatment of patients suspected of DSD conditions include clinical examination, measurement of peptide and steroid hormones, and genetic analysis. This position paper on peptide hormone analyses in the diagnosis and control of patients with DSD was jointly prepared by specialists in the field of DSD and/or peptide hormone analysis from the European Cooperation in Science and Technology (COST) Action DSDnet (BM1303) and the European Reference Network on rare Endocrine Conditions (Endo-ERN). The goal of this position paper on peptide hormone analysis was to establish laboratory guidelines that may contribute to improve optimal diagnosis and treatment control of DSD. The essential peptide hormones used in the management of patients with DSD conditions are follicle-stimulating hormone, luteinising hormone, anti-Müllerian hormone, and Inhibin B. In this context, the following position statements have been proposed: serum and plasma are the preferred matrices; the peptide hormones can all be measured by immunoassay, while use of LC-MS/MS technology has yet to be implemented in a diagnostic setting; sex- and age-related reference values are mandatory in the evaluation of these hormones; and except for Inhibin B, external quality assurance programs are widely available.

DIAGNOSIS OF ENDOCRINE DISEASE: Drug-induced endocrinopathies and diabetes: a combo-endocrinology overview.

In the currently overwhelming era of polypharmacy, the balance of the dynamic and delicate endocrine system can easily be disturbed by interfering pharmaceutical agents like medications. Drugs can cause endocrine abnormalities via different mechanisms, including direct alteration of hormone production, changes in the regulation of the feedback axis, on hormonal transport, binding and signaling, as well as similar changes to counter-regulatory hormone systems. Furthermore, drugs can interfere with the hormonal assays, leading to erroneous laboratory results that disorientate clinicians from the right diagnosis. The purpose of this review is to cover a contemporary topic, the drug-induced endocrinopathies, which was presented in the monothematic annual Combo Endo Course 2018. This challenging part of endocrinology is constantly expanding particularly during the last decade, with the new oncological therapeutic agents, targeting novel molecular pathways in the process of malignancies. In this new context of drug-induced endocrine disease, clinicians should be aware that drugs can cause endocrine abnormalities via different mechanisms and mimic a variety of clinical scenarios. Therefore, it is extremely important for clinicians not only to promptly recognize drug-induced hormonal and metabolic abnormalities, but also to address the therapeutic issues for timely intervention.

Somatostatin analogues suppress the inflammatory reaction in vivo.

Somatostatin (Sms) and its agonist analogues inhibit the secretory activities of endocrine and neural cells. Recent studies have suggested that Sms has significant immunomodulatory properties. In this study, we examine the effects of two Sms octapeptide analogues on the inflammatory reaction in vivo. BIM 23014 (Somatulin) and Sandostatin were administered to male Sprague-Dawley rats subject to carrageenin-induced aseptic inflammation, at doses of 2-10 micrograms/rat, given either systemically or locally. Animals were killed 7 h after the induction of the inflammation, and the inflammatory exudates were aspirated and quantitated in terms of volume and leukocyte concentration. Sms analogues, administered via either route, significantly reduced the volume and the leukocyte concentration of the exudate in a time- and dose-dependent fashion. In corroboration of these, immunohistochemical evaluation of the levels of local inflammatory mediators, such as immunoreactive (Ir) TNF-alpha, Irsubstance P, and Ircorticotropin-releasing hormone, was inhibited significantly by Sms analogue treatment. These findings suggest that Sms analogues have significant antiinflammatory effects in vivo, associated with suppression of proinflammatory cytokines and neuropeptides. Furthermore, these data suggest that Sms agonists may be useful in the control of inflammatory reaction.

Immunoreactive corticotropin-releasing hormone and its binding sites in the rat ovary.

Corticotropin-releasing hormone (CRH), the principal neuropeptide regulator of pituitary ACTH secretion, is also produced at peripheral inflammatory sites, where it acts as a proinflammatory cytokine, and by the Leydig cell of the testis, where it exerts autocrine inhibition of testosterone biosynthesis. Because key ovarian functions, such as ovulation and luteolysis, represent aseptic inflammatory responses, and because the theca cell is the functional equivalent of the Leydig cell, we explored the CRH presence in the ovary, first, by specific CRH immunohistochemistry of adult cycling female Sprague-Dawley rat ovaries. We detected cytoplasmic immunoreactive CRH (IrCRH) in theca and stromal cells and in cells within the corpora lutea, at all phases of the estrous cycle. Using a specific radioimmunoassay, we measured IrCRH in extracts of rat ovaries (0.042-0.126 pmol/g wet tissue). The mobility of the ovarian IrCRH molecule was similar to that of rat/human CRH by reverse phase HPLC. To investigate the CRH action in the ovary, we identified, characterized, and localized CRH receptors in the rat ovary. Binding was linear with increasing tissue concentration, saturable, and of high affinity. Scatchard analysis of 125I-Tyr-ovine CRH competitive displacement curves indicated a high affinity binding site with a Kd of approximately 6 nM and a Bmax value of approximately 61 fM/mg protein. Autoradiographic studies revealed CRH receptors primarily in ovarian theca and stroma. We conclude that IrCRH and CRH receptors are present in rat ovaries, suggesting that this neuropeptide may play a regulatory role in this gonad, perhaps through its proinflammatory properties and/or by participating in the auto/paracrine regulation of steroid biosynthesis. Functional studies are necessary to define the role(s) of CRH in the ovary.

Positive association of serum interleukin-1beta and CRH levels in women with pre-term labor.

OBJECTIVE: The aim of this study was to investigate the hypothesis that interleukin-1beta (IL-1beta) might be involved in the increase of the circulating levels of placental-derived CRH leading to the initiation of pre-term labor. SUBJECTS AND METHODS: Forty-eight primigravidae with a singleton viable pregnancy between 28 and 34 weeks of gestation were studied. The subjects were divided in two groups: group A consisted of 30 pregnant women (mean age+/-SD; 22+/-1.1 yr old) presented with pre-term labor (mean gestational age+/-SD; 30.6+/-2.3 weeks) and group B consisted of 18 pregnant women (24+/-2.6 yr old) with normal pregnancies (29.8+/-3.1 weeks). CRH and IL-1beta levels were measured in blood specimens collected from all the study subjects on admission. RESULTS: Women of group A presented significantly higher serum CRH levels (mean+/-SE; 1.18+/-1.83 ng/ml) compared to those of group B (0.48+/-0.67 ng/ml) (p<0.01). Similarly, serum IL-1beta levels were significantly higher in women of group A (0.45+/-0.12 pg/ml) compared to those of group B (0.31+/-0.08 pg/ml) (p<0.01). A positive correlation was found between serum IL-1beta and CRH (r=0.68, p=0.001) in women of group A (pre-term labor). CONCLUSIONS: Our findings suggest that the increased levels of IL-1beta and CRH found in pregnant women presented with pre-term labor might be involved in the pathophysiologic mechanism of the latter. Furthermore, a positive interaction might exist between IL-1beta and placental CRH which might lead to enhanced production of the second, facilitating, thus, the onset of labor.

Effect of endocrine disruptors on male reproduction in humans: why the evidence is still lacking?

The so-called "endocrine disruption hypothesis" suggests that exposures to endocrine disruption (EDs) during fetal, neonatal and adult life may interfere with the development of reproductive organs and alter semen quality and reproductive hormone production. Even though animal studies provide substantial evidence of adverse effects of EDs on male reproductive system, epidemiological studies in humans arrive at conflicting results. The aim of the present study was to systematically review the literature to locate methodological characteristics of the studies that struggle the formation of an association between EDs and human male reproduction. Such characteristics include: (i) definition of the exposed and the non-exposed population, (ii) age, (iii) insufficient control for confounders, (iv) ED assay and threshold, (v) time parameters of ED exposure, and (vi) study outcomes. Additional issues are: (i) the late effect of an early exposure, (ii) the multiple exposure effect, and (iii) the fact the same ED may exhibit different modes of action. Unfortunately, the nature of the field precludes the conduction of randomized-controlled trials, which could result to etiological associations between EDs and human male reproduction. Consequently, there is a great need to conduct well-designed studies of case-control or cohort type to evaluate EDs effects on human male reproductive health, and apply possible measures that could limit dangerous exposures.

Dysregulation of 11beta-hydroxysteroid dehydrogenases: implications during pregnancy and beyond.

Glucococorticoids play a critical role in the developmental programing and fetal growth. Key molecules mediating and regulating tissue-specific glucocorticoid actions are 11beta-hydroxysteroid dehydrogenase (11beta-HSD) type 1 and 2 isozymes, both of which are expressed in the placenta and the fetal membranes. 11beta-HSD1 is implicated in the pathogenesis of metabolic syndrome and its dysregulation has been observed in pregnancy-related complications (pre-eclampsia, intrauterine growth restriction). Interestingly, preliminary clinical data have associated certain 11beta-HSD1 gene polymorphisms with hypertensive disorders in pregnancy, suggesting, if confirmed by further targeted studies, it's potential as a putative prognostic marker. Animal studies and observations in humans have confirmed that 11beta-HSD2 insufficiency is related with pregnancy adversity (pre-eclampsia, intrauterine growth restriction, preterm birth). Importantly, down-regulation or deficiency of placental 11beta-HSD2 is associated with significant restriction in fetal growth and low-birth weight, and unfavorable cardio-metabolic profile in adulthood. The potential association of 11beta-HSD1 tissue-specific dysregulation with gestational diabetes, as well as the plausible utility of 11beta-HSD2, as a biomarker of pregnancy adversity and later life morbidity, are emerging areas of intense scientific interest and future investigation.

No association between insulin resistance and preeclampsia.

OBJECTIVE: To investigate the possible link between insulin resistance and preeclampsia. METHODS: The study included 30 primigravidas between 28 and 34 weeks of gestation. The study subjects were divided into two groups: Group A consisted of 15 normotensive women of a mean gestational age of 31.6 weeks and group B consisted of 15 preeclamptic women of a mean gestational age of 29.9 weeks. Glucose and insulin levels were measured at 0, 1 and 2 h of an OGTT (after 75 g oral glucose administration). Insulin resistance and sensitivity were evaluated with the use of IR HOMA, QUICKI and IS OGTT. RESULTS: Glucose and insulin levels at 0, 1 and 2 h of the OGTT as well as IR HOMA, QUICKI and IS OGTT were comparable between preeclamptic and normotensive pregnant women. CONCLUSIONS: Our results indicate that preeclampsia is not associated with hyperinsulinaemia and/or insulin resistance, in either the fasting or the postprandial state.

Somatostatin may participate in the antiinflammatory actions of glucocorticoids.

Glucocorticoids are potent antiinflammatory agents. They inhibit leukocyte chemotaxis and vascular permeability and generally suppress the expression of many inflammatory mediators. Recent reports suggested that somatostatin (Sms) had significant immunomodulatory properties in vitro and in vivo. In this study we examined the effects of glucocorticoids on immunoreactive somatostatin expression in aseptic inflammatory sites of Sprague-Dawley rats given carrageenin sc. The progress of the inflammatory reaction was studied over a 7-h period with respect to the volume and cellularity of the exudate and the levels of the inflammatory mediators expressed in the inflammatory site, including immunoreactive substance P (sP), corticotropin-releasing hormone (CRH), and tumor necrosis factor-alpha (TNF alpha). Dexamethasone significantly reduced the volume and cellularity of the inflammatory exudates; in parallel, the levels of immunoreactive sP, CRH, and TNF alpha were significantly suppressed by this glucocorticoid. In contrast, immunoreactive Sms was stimulated by dexamethasone in a time-dependent fashion. These findings suggest another mechanism for suppression of the inflammatory reaction by glucocorticoids via stimulation of local Sms expression, which occurs in parallel to the inhibition of the local inflammatory mediators sP, CRH, and TNF alpha.

Immune corticotropin-releasing hormone is present in the eyes of and promotes experimental autoimmune uveoretinitis in rodents.

We examined the presence and potential role of local corticotropin-releasing hormone (CRH) in experimental uveitis in rodents. This 41-amino acid peptide, originally isolated from the hypothalamus, is also secreted locally in experimentally induced and natural inflammatory sites, where it exerts autocrine or paracrine proinflammatory effects. Female Lewis rats were immunized with the major pathogenic epitope (R16 peptide) of the interphotoreceptor retinoid-binding protein in complete Freund's adjuvant, monitored daily, and killed 8, 9, 10, 12, 14, or 18 days later, after having developed uveoretinitis. Immunoreactive CRH (IrCRH) was detected by immunohistochemistry in the uveitic eyes in the cytoplasm of inflammatory cells (macrophages, lymphocytes, and polymorphonuclear cells) infiltrating the iris, ciliary body, vitreous, retina, and choroid depending on the stage of the disease. The intensity of the IrCRH staining was positively correlated with the severity of the disease based on morphological criteria. The amount of IrCRH measured by RIA varied between 0.18 +/- 0.03 (mean +/- SE) and 0.79 +/- 0.07 pmol/g wet tissue (8th and 14th day of the disease, respectively). Ophthalmic IrCRH in uveitic rat eyes had similar chromatographic mobility as rat/human CRH-(1-41) by HPLC. Furthermore, female B10.A mice were immunized with interphotoreceptor retinoid-binding protein and treated during the induction (0-7 days) or expression (8-16 days) stages of the disease with ip injections of the anti-CRH antibody TS-2 or placebo nonimmune rabbit serum. The early anti-CRH treatment significantly decreased the disease intensity compared to that in placebo- or late-treated animals (P < 0.05, by analysis of variance). We conclude that IrCRH is present at the site of inflammation in rodent experimental uveitis and that its expression correlates with the natural history and intensity of the disease. Immune CRH appears to play an early pathogenetic role in the induction of experimental uveitis.

Corticotropin-releasing hormone (CRH) inhibits steroid biosynthesis by cultured human granulosa-lutein cells in a CRH and interleukin-1 receptor-mediated fashion.

The presence of immunoreactive CRH was recently demonstrated in human ovaries. CRH immunoreactivity was localized by immunohistochemistry in the cytoplasm of thecal cells surrounding the ovarian follicles, in luteinized cells of the stroma, and in large granulosa-derived luteinized cells of developing corpora lutea. Also, CRH and its receptors were identified in Leydig cells of the testis where CRH was shown to inhibit testosterone biosynthesis. To examine the role of CRH in the ovary, we studied its effect on estradiol (E2) and progesterone (P4) release by human granulosa cells obtained from women undergoing in vitro fertilization for male factor infertility or uni- or bilateral tubal impatency. In all subjects, superovulation was induced by treatment with gonadotropins. The effects of graded doses of ovine CRH (10[-11]-10[-6] mol/liter) were evaluated in the conditioned medium obtained after 24 h incubation of the cells. All CRH concentrations employed except for the lowest one (10[-11] mol/liter) caused a significant decrease of media E2 and P4 levels. Maximal inhibition for both E2 and P4 production was obtained by 10[-6] mol/liter CRH concentration, which decreased hormone production by 39% and 34%, respectively. The alpha-helical CRH9-41 antagonist at 10(-6) and 10(-7) mol/liter blocked the suppressive effect of 10(-9) mol/liter CRH on both E2 and P4 secretion, while it had no effect when added to the culture media without CRH. Since interleukin (IL-1)-1 mediates certain actions of CRH on leukocytes, we examined whether the CRH effect on ovarian steroidogenesis was IL-1-mediated. Interleukin-1 receptor antagonist at 10(-7) and 10(-6) mol/liter blocked the inhibitory effects of CRH on E2 and P4 secretion, while it had no effect in the absence of CRH. In conclusion, CRH exerts a CRH- and IL-1 receptor-mediated inhibitory effect on ovarian steroidogenesis and might be actively involved in the still enigmatic processes of follicular atresia and luteolysis.

Recombinant interleukin-6 activates the hypothalamic-pituitary-adrenal axis in humans.

The inflammatory cytokines, tumor necrosis factor-alpha, interleukin-1 alpha and -beta (IL-1 alpha and -beta), and IL-6 can activate the hypothalamic-pituitary-adrenal (HPA) axis. Tumor necrosis factor-alpha and IL-1 have been tested in both experimental animals and humans, but their administration has been limited by significant toxicity, mainly severe hypotension. IL-6, on the other hand, has demonstrated modest toxicity in animals. We evaluated the ability of recombinant IL-6 to stimulate the human HPA axis in patients with cancer and a good performance status, who received daily morning sc injections of 30 micrograms/kg IL-6 for 7 consecutive days, during the course of a phase I trial. IL-6 caused impressively marked and prolonged elevations of plasma ACTH and cortisol on the first day and blunted ACTH responses on the seventh day of treatment, perhaps as a result of increased baseline cortisol levels. The overall cortisol response, however, on the seventh day was of similar magnitude, suggesting that a new equilibrium in the feedback regulation of the HPA axis occurs with chronic IL-6 administration. The toxic effects of IL-6 were modest, suggesting that it might be useful for clinical testing of the HPA axis, as an alternative to the insulin tolerance test.