Erdheim-Chester disease with rare radiological features in a 14-year old girl with pre-B Acute Lymphocytic Leukemia and Diabetes Mellitus

We report a case of a 14 year-old girl with Diabetes Mellitus who was in remission with pre-B cell Acute Lymphoblastic Leukemia and subsequently diagnosed with Erdheim-Chester disease. Erdheim-Chester disease is a non-Langerhans cell histiocytosis and is very rare in children. In addition, the radiological features of the lesions are atypical and have not been reported in children. There is no known association between the three conditions and this is the first reported case in the literature. A literature review of Erdheim-Chester disease will be performed.

Primary human chorionic gonadotropin secreting germinoma of the corpus callosum

Background:

Primary intracranial germinomas are a rare subset of intracranial tumors derived from mis-incorporated germ cells within the folding neural plate during embryogenesis. Though known to arise from midline structures in the central nervous system (CNS), occurrence within the corpus callosum is exceedingly rare.

Case Description:

We present a rare case of secreting primary intracranial germinoma with extensive intraventricular metastasis presenting as a multi-cystic butterfly lesion in the genu of the corpus callosum in a young boy.

Conclusion:

Intracranial germ cell tumors must be considered for any multi-cystic lesion arising from midline structures in the CNS in the preadult population.

Effects of chromium picolinate supplementation on insulin sensitivity, serum lipids, and body composition in healthy, nonobese, older men and women

BACKGROUND

Chromium is an essential nutrient required for carbohydrate and lipid metabolism. Chromium supplementation in humans has been reported to improve glucose metabolism and improve serum lipid parameters and to reduce body fat; parameters that worsen with aging. As a result, chromium picolinate has been widely promoted as a health aid for the general population. The purpose of the study was to examine the effects of chromium supplementation on insulin sensitivity, serum lipids, and body composition in nonobese, healthy men and women of advanced age.

METHODS

A randomized, double-blind, placebo-controlled study with 19 subjects (9 men and 10 women), aged 63-77, were given either chromium picolinate, 1,000 microg/d, or a placebo for 8 weeks. Serum lipids were measured at baseline and 8 weeks. Insulin sensitivity and body composition were measured with the minimal-model intravenous glucose tolerance test and dual-energy x-ray absorptiometry scan, respectively, at baseline and after 8 weeks of chromium or placebo supplementation.

RESULTS

No significant change in serum lipids, insulin sensitivity, or body composition was observed in the chromium group compared with the placebo group.

CONCLUSIONS

Chromium picolinate supplementation alone does not appear to improve insulin sensitivity, serum lipids, or change body composition in nonobese, healthy men and women of advanced age.

The insulin-like growth factor system in the GT1-7 GnRH neuronal cell line

Evidence suggests that insulin-like growth factors (IGFs; IGF-I and IGF-II) are involved in the regulation of reproductive function including the development of the gonadotropin-releasing hormone (GnRH) neuronal system and the modulation of GnRH secretory activities. To further characterize the regulatory role of the IGF system on GnRH neuronal function, we have examined the gene expression of IGF-I, IGF-II, IGF-I receptor (IGF-IR), and IGF-binding proteins (IGFBPs) in a GnRH neuronal cell line (GT1-7 cells). The relative effects of IGFs and insulin on GnRH secretion by these cells was also investigated. RT-PCR analysis demonstrated IGF-I, IGF-II and IGF-IR mRNAs in GT1-7 cells. The mRNAs for IGFBP-2, -3, -4, -5 and -6 but not IGFBP-1 were also detected. Immunoreactive protein bands for IGFBP-2, -4 and -5 but not for other IGFBPs were demonstrated by Western blot with IGFBP-5 appearing to be the most abundant IGFBP secreted by GT1-7 cells. IGFBP-5 production by GT1-7 cells was stimulated by both IGF-I and IGF-II in a dose-dependent manner with approximately equal potency, whereas insulin caused no significant effect. GnRH secretion by GT1-7 cells treated with IGF-I or IGF-II but not insulin showed an increase (80-100%) at 2 h of treatment followed by a decrease (46%) at 6 h that continued up to 24 h. We conclude that the expression of IGFs, IGF-IR and IGFBPs and their interactions in the regulation of GnRH secretion by GT1-7 cells as demonstrated by our study provide a basis for an autocrine regulatory role for the IGF system in GnRH neuronal secretory activities.

Neurosteroidogenesis in astrocytes, oligodendrocytes, and neurons of cerebral cortex of rat brain

The brain is a steroidogenic organ that expresses steroidogenic enzymes and produces neurosteroids. Although considerable information is now available regarding the steroidogenic capacity of the brain, little is known regarding the steroidogenic pathway and relative contributions of astrocytes, oligodendrocytes, and neurons to neurosteroidogenesis. In the present study, we investigated differential gene expression of the key steroidogenic enzymes using RT-PCR and quantitatively evaluated the production of neurosteroids by highly purified astrocytes, oligodendrocytes, and neurons from the cerebral cortex of neonatal rat brains using specific and sensitive RIAs. Astrocytes appear to be the most active steroidogenic cells in the brain. These cells express cytochrome P450 side-chain cleavage (P450scc), 17alpha-hydroxylase/C17-20-lyase (P450c17), 3beta-hydroxysteroid dehydrogenase (3betaHSD), 17beta-hydroxysteroid dehydrogenase (17betaHSD), and cytochrome P450 aromatase (P450arom) and produce pregnenolone (P5), progesterone (P4), dehydroepiandrosterone (DHEA), androstenedione (A4), testosterone (T), estradiol, and estrone. Oligodendrocytes express only P450scc and 3betaHSD and produce P5, P4, and A4. These cells do not express P450c17, 17betaHSD, or P450arom or produce DHEA, T, or estrogen. Neurons express P450scc, P450c17, 3betaHSD, and P450arom and produce P5, DHEA, A4, and estrogen, but do not express 17betaHSD or produce T. By comparing the ability of each cell type in the production of neurosteroids, astrocytes are the major producer of P4, DHEA, and androgens, whereas oligodendrocytes are predominantly the producer of P5 and neurons of estrogens. These findings serve to define the neurosteroidogenic pathway, with special emphasis on the dominant role of astrocytes and their interaction with oligodendrocytes and neurons in the genesis of DHEA and active sex steroids. Thus, we propose that neurosteroidogenesis is accomplished by a tripartite contribution of the three cell types in the brain.

Dehydroepiandrosterone: biosynthesis and metabolism in the brain

Dehydroepiandrosterone (DHEA) is abundantly found in brain tissues of several species, including human. However, the cellular origin and pathway by which DHEA is synthesized in brain are not yet known. We have, therefore, initiated pilot experiments to explore gene expression of cytochrome P450 17alpha-hydroxylase (P450c17), the key steroidogenic enzyme for androgen synthesis, and evaluate DHEA production by highly purified astrocytes, oligodendrocytes, and neurons. Using RT-PCR, we have demonstrated for the first time that astrocytes and neurons in the cerebral cortex of neonatal rat brain express P450c17. The presence of P450c17 in astrocytes and neurons was supported by the ability of these cells to metabolize pregnenolone to DHEA in a dose-dependent manner as determined by RIA. These data were further confirmed by production of androstenedione by astrocytes using progesterone as a substrate. However, cortical neurons express a low transcript of P450c17 messenger RNA and produce low levels of DHEA and androstenedione compared with astrocytes. Oligodendrocytes neither express the messenger RNA nor produce DHEA. The production of DHEA by astrocytes is not limited to cerebral cortex, as hypothalamic astrocytes produce DHEA at a level 3 times higher than that produced by cortical astrocytes. Cortical and hypothalamic astrocytes also have the capacity to metabolize DHEA to testosterone and estradiol in a dose-dependent manner. However, hypothalamic astrocytes were 3 times more active than cortical astrocytes in the metabolism of DHEA to estradiol. In conclusion, our data presented evidence that astrocytes and neurons express P450c17 and synthesize DHEA from pregnenolone. Astrocytes also have the capacity to metabolize DHEA into sex steroid hormones. These data suggest that as in gonads and adrenal, DHEA is biosynthesized in the brain by a P450c17-dependent mechanism.

Effects of lifestyle and body composition on the ovary

Reduction of metabolic fuel availability below the critical level by food restriction or increased expenditure is appropriately accompanied by activations of multiple neuroendocrine-metabolic changes resulting in anovulation and amenorrhea, an important device for endogenous hypothalamic contraception. This reproductive strategy in women is required because of the enormous nutritional demand for reproductive success.

Aging and the adrenal cortex

Aging in humans is accompanied by an increase in adrenal glucocorticoid secretion and a decline in adrenal androgen synthesis and secretion. The intense interest in adrenal function in aging individuals in recent years is in large measure related to the potential impact of cortisol excess in the development of cognitive impairment and hippocampal neuronal loss, and to the desire to provide hormone replacement and healthy aging. Although the preliminary data is tantalizing, solid scientific evidence are not at hand. It is apparent that both issues are extremely complex. Dehydroepiandrosterone (DHEA) and its 3 beta-sulfate are fascinating molecules, including their synthesis and actions in the brain. Recent studies have shown that DHEA-sulfate (DHEA-S), but not DHEA, activates peroxisome proliferator-activated receptor alpha (PPAR alpha) in the liver, an intracellular receptor belonging to the steroid receptor superfamily. Thus, DHEA-S may serve as a physiological modulator of liver fatty acid metabolism and peroxisomal enzyme expression, and thereby may contribute to the anticarcinogenic and chemoprotective properties of this intriguing class of endogenous steroids. The life-sustaining role of adrenal cortisol secretion and its regulation of metabolism via catabolic actions may be modulated by its partner DHEA and DHEA-S. During the anabolic growth period (childhood and early adulthood) the body is exposed to relatively high levels of DHEA/DHEA-S but to relatively or absolutely high levels of cortisol during infancy and the aging phase. The cortisol/DHEA-S ratio during the life span follows a U-shape curve, which may be telling us to explore these two critical adrenal steroids in tandem.

Racial differences in renal kallikrein excretion: effect of the ovulatory cycle

BACKGROUND

Renal kallikrein excretion is diminished in essential hypertension, especially in African-Americans, and evidence exists for a major gene effect on the kallikrein phenotype. In addition, urinary kallikrein excretion differs by gender, with ovulating females having greater kallikrein excretion than males or postmenopausal females. Recent studies have shown that renal kallikrein excretion varies in females during the ovulatory cycle, with levels rising during the luteal phase and returning during the follicular phase to levels that are similar to those of males. In family studies, gender differences in urinary kallikrein excretion were present in white subjects, but not black subjects. We therefore hypothesized dysregulation of kallikrein biosynthetic responses in African-Americans.

METHODS

We determined urinary kallikrein activity [chromogenic substrate S2266 (D-val-leu-arg-paranitroanilide) assay; in microU/mg creatinine] in white (N = 15) and black (N = 11) ovulating females during the ovulatory cycle. Serum progesterone, estrogen, plasma renin activity as well as urinary aldosterone, and urinary electrolytes were determined to investigate changes between mid-follicular and mid-luteal phases in the two groups.

RESULTS

White and black groups were matched for age, body mass index, blood pressure, heart rate and renal function. Ovulatory cycle phases were confirmed by serum progesterone determinations, which increased significantly in whites and blacks to a comparable degree [0.84 +/- 0.14 nmol/liter (mid-follicular) to 29.77 +/- 4.70 nmol/liter (mid-luteal) in whites, 0.67 +/- 0.08 nmol/liter (mid-follicular) to 28.62 +/- 5.83 nmol/liter (mid-luteal) in blacks; P < 0.001 for cycle effect, P = NS for race effect and race X cycle interaction]. Urinary kallikrein activity increased from 623 +/- 86 microU/mg creatinine (mid-follicular) to 948 +/- 142 microU/mg creatinine (mid-luteal) in whites, but did not change in blacks during the ovulatory cycle [239 +/- 73 microU/mg creatinine (mid-follicular] to 244 +/- 41 microU/mg creatinine (mid-luteal)]. Two-way ANOVA revealed significant effects on urinary kallikrein for race (P < 0.001), cycle (P < 0.05), and race X cycle interaction (P < 0.05). Thus, white females had higher urinary kallikrein than black females, and demonstrated a significant increase in urinary kallikrein excretion during the ovulatory cycle, whereas no significant change in urinary kallikrein activity was seen in the black group. Enzyme kinetic studies and mixing studies demonstrated that these racial differences in renal kallikrein excretion were quantitative, rather than due to qualitative differences in the renal kallikrein enzyme or due to the presence of a kallikrein inhibitor.

CONCLUSIONS

These results suggest pronounced blunting of menstrual cycle changes in urinary kallikrein excretion in black females. Blunted urinary kallikrein responses during the ovulatory cycle are consistent with dysregulation of renal kallikrein biosynthetic responses in African-Americans, a group at increased risk for hypertension.

The effect of six months treatment with a 100 mg daily dose of dehydroepiandrosterone (DHEA) on circulating sex steroids, body composition and muscle strength in age-advanced men and women

OBJECTIVE

The biological role of the adrenal sex steroid precursors--DHEA and DHEA sulphate (DS) and their decline with ageing remains undefined. We observed previously that administration of a 50 daily dose of DHEA for 3 months to age-advanced men and women resulted in an elevation (10%) of serum levels of insulin-like growth factor-I (IGF-I) accompanied by improvement of self-reported physical and psychological well-being. These findings led us to assess the effect of a larger dose (100 mg) of DHEA for a longer duration (6 months) on circulating sex steroids, body composition (DEXA) and muscle strength (MedX).

SUBJECTS AND DESIGN

Healthy non-obese age-advanced (50-65 yrs of age) men (n = 9) and women (n = 10) were randomized into a double-blind placebo-controlled cross-over trial. Sixteen subjects completed the one-year study of six months of placebo and six months of 100 mg oral DHEA daily.

MEASUREMENTS

Fasting early morning blood samples were obtained. Serum DHEA, DS, sex steroids, IGF-I, IGFBP-1, IGFBP-3, growth hormone binding protein (GHBP) levels and lipid profiles as well as body composition (by DEXA) and muscle strength (by MedX testing) were measured at baseline and after each treatment.

RESULTS

Basal serum levels of DHEA, DS, androsternedione (A), testosterone (T) and dihydrotestosterone (DHT) were at or below the lower range of young adult levels. In both sexes, a 100 mg daily dose of DHEA restored serum DHEA levels to those of young adults and serum DS to levels at or slightly above the young adult range. Serum cortisol levels were unaltered, consequently the DS/cortisol ratio was increased to pubertal (10:1) levels. In women, but not in men, serum A, T and DHT were increased to levels above gender-specific young adult ranges. Basal SHBG levels were in the normal range for men and elevated in women, of whom 7 of 8 were on oestrogen replacement therapy. While on DHEA, serum SHBG levels declined with a greater (P < 0.02) response in women (-40 +/- 8%; P = 0.002) than in men (-5 +/- 4%; P = 0.02). Relative to baseline, DHEA administration resulted in an elevation of serum IGF-I levels in men (16 +/- 6%, P = 0.04) and in women (31 +/- 12%, P = 0.02). Serum levels of IGFBP-1 and IGFBP-3 were unaltered but GHBP levels declined in women (28 +/- 6%; P = 0.02) not in men. In men, but not in women, fat body mass decreased 1.0 +/- 0.4 kg (6.1 +/- 2.6%, P = 0.02) and knee muscle strength 15.0 +/- 3.3% (P = 0.02) as well as lumbar back strength 13.9 +/- 5.4% (P = 0.01) increased. In women, but not in men, an increase in total body mass of 1.4 +/- 0.4 kg (2.1 +/- 0.7%; P = 0.02) was noted. Neither gender had changes in basal metabolic rate, bone mineral density, urinary pyridinoline cross-links, fasting insulin, glucose, cortisol levels or lipid profiles. No significant adverse effects were observed.

CONCLUSIONS

A daily oral 100 mg dose of DHEA for 6 months resulted in elevation of circulating DHEA and DS concentrations and the DS/cortisol ratio. Biotransformation to potent androgens near and slightly above the range of their younger counterparts occurred in women with no detectable change in men. Given this hormonal milieu, an increase in serum IGF-I levels was observed in both genders but dimorphic responses were evident in fat body mass and muscle strength in favour of men. These differences in response to DHEA administration may reflect a gender specific response to DHEA and/or the presence of confounding factor(s) in women such as oestrogen replacement therapy.

Lack of insulin resistance in fibroblasts from subjects with polycystic ovary syndrome

Insulin resistance in polycystic ovary syndrome (PCOS) is characterized by a novel defect in insulin signal transduction expressed in isolated human adipocytes as impaired insulin sensitivity for glucose transport and antilipolysis. To determine whether this is a generalized defect of a potentially genetic basis, or possibly a tissue-specific one, fibroblast cultures were established from age- and weight-matched obese normal cycling (NC; n = 5) and PCOS (n = 6) subjects. Adipocytes from the current PCOS subjects displayed impaired sensitivity for glucose transport stimulation (half-maximal effective concentration [EC50], 317 +/- 58 pmol/L in PCOS v 130 +/- 40 in NC; P < .025). Specific insulin binding was similar in fibroblasts from NC (0.57% +/- 0.10%/10(6) cells) and PCOS (0.45% +/- 0.10%) subjects. Fibroblasts from NC (4.9- +/- 0.5-fold stimulation) and PCOS (4.6- +/- 0.3-fold) subjects were equally responsive to insulin for stimulation of glucose incorporation into glycogen. Insulin sensitivity for glycogen synthesis in fibroblasts did not differ between NC (EC50, 9.6 +/- 0.9 nmol/L) and PCOS (9.1 +/- 0.9) cells. For thymidine incorporation into DNA, relative insulin responsiveness was similar in NC (2.3- +/- 0.3-fold stimulation) and PCOS (2.1- +/- 0.1-fold) fibroblasts. Insulin sensitivity for DNA synthesis was similar in NC (EC50, 12.9 +/- 2.4 nmol/L) and PCOS (7.6 +/- 1.3) cells. In summary, (1) insulin receptor binding is normal in PCOS fibroblasts; and (2) PCOS fibroblasts have normal insulin sensitivity and responsiveness for metabolic and mitogenic responses. Impaired insulin signal transduction, while present in adipocytes from a group of PCOS subjects, is not found in fibroblasts from the same subjects. This defect is not generalized to all cell types, but may be limited to specific tissues and responses.

Preliminary report on the treatment of endometriosis with low-dose mifepristone (RU 486)

OBJECTIVE

We have previously shown that treatment with mifepristone, 50 to 100 mg daily, results in amenorrhea, anovulation, and symptomatic improvement in women with endometriosis. In this study we lowered the dose to 5 mg daily to determine whether clinical efficacy is altered without other adverse actions.

STUDY DESIGN

After a baseline cycle, seven women with endometriosis were given mifepristone, 5 mg daily, for 6 months. Daily symptom inventories were recorded. Laparoscopy was performed during the sixth month of therapy.

RESULTS

Pelvic pain improved in six of seven patients. Cyclic bleeding ceased in all patients, but four of the seven patients complained of irregular bleeding. Surgical staging at the conclusion of the study (five of seven patients) did not detect a change in endometriosis.

CONCLUSIONS

Mifepristone, 5 mg daily, resulted in symptomatic improvement, but did not stabilize the endometrium. From our experience with three doses of mifepristone, we would recommend a dose of 50 mg be used for continued investigations.

Corticotropin-releasing factor inhibits luteinizing hormone-stimulated P450c17 gene expression and androgen production by isolated thecal cells of human ovarian follicles

Recently, we reported that the thecal compartment of the human ovary contains a CRF system replete with gene expression and protein for corticotropin-releasing factor (CRF), CRF-Receptor 1 (CRF-R1), and the blood-derived high affinity CRF binding protein (CRF-BP). Granulosa cells are devoid of the CRF system. The parallel increases in intensity of CRF, CRF-R1, and 17 alpha-hydroxylase messenger ribonucleic acid (mRNA) and proteins in thecal cells with follicular maturation suggest that the intraovarian CRF system may play an autocrine role regulating androgen biosynthesis, with a downstream effect on estrogen production by granulosa cells. The functionality of the ovarian CRF system may be conditioned by the relative presence of plasma-derived CRF-BP by virtue of its localization of protein, but not transcript in thecal cells and its ability to compete with CRF for the CRF receptor. To further these findings, in the present study we have examined the effect of CRF on LH-stimulated 17 alpha-hydroxylase (P450c17) gene expression and androgen production by isolated thecal cells from human ovarian follicles (11-13 mm). During the 48-h culture, addition of LH (10 ng/mL) to the medium increased by 5- and 6-fold dehydroepiandrosterone and androstenedione production by thecal cells. Remarkably, the LH-stimulated, but not basal, androgen production was inhibited by CRF in a time- and dose-dependent manner. The half-maximal (ID50) effect dose of CRF occurred at 5 x 10(-8) mol/L, and at a maximal concentration of 10(-6) mol/L, CRF completely inhibited LH-stimulated androgen production. This inhibitory effect of CRF became evident at 12 h (45%), and by 24 h the effect was more pronounced, with a 70% reduction from baseline. As determined by Northern analyses, CRF dose dependently decreased LH-stimulated P450c17 mRNA levels, with a maximal inhibition of 85% P450c17 gene expression at a CRF concentration of 10(-6) mol/L. With the addition of 10(-6) mol/L of the antagonist alpha-helical CRF-(9-41), the inhibitory effect of CRF was partially reversed for both P450c17 mRNA (75%) and androgen production (50%), indicating the CRF-R1-mediated event. In conclusion, the present study demonstrated a potent inhibitory effect of CRF on LH-stimulated dehydroepiandrosterone and androstenedione production that appears to be mediated through the reduction of P450c17 gene expression. Thus, the ovarian CRF system may function as autocrine regulators for androgen biosynthesis in the thecal cell compartment to maintain optimal substrate for estrogen biosynthesis by granulosa cells. Further studies to define the role of CRF-BP in the endocrine modulation of the intraovarian CRF system are needed.

Nutritional and endocrine-metabolic aberrations in women with functional hypothalamic amenorrhea

The development of functional hypothalamic amenorrhea (FHA) in weight-stable, nonathletic women has long been thought to be psychogenic in origin. This study was designed to gain insight into the possibility that nutritional deficits and compensatory endocrine-metabolic adaptations contribute to the development and maintenance of FHA of the psychogenic type. Nutritional intake, insulin sensitivity, and 24-h dynamics of insulin/glucose, cortisol, leptin, somatotropic, and LH axes were simultaneously assessed in eight women with FHA not associated with exercise or weight loss and in eight age- and body mass index-matched regular cycling controls (NC). The percent fat body mass was lower and lean body mass was higher in FHA than in NC (P < 0.05). The FHA subjects scored higher (P < 0.05) on two Eating Disorder Inventory subscales and had a higher (P < 0.05) Beck depression rating than NC, although all were in the subclinical range. Although daily caloric intake did not differ, FHA consumed 50% less (P < 0.001) fat, twice (P < 0.05) as much fiber, and more carbohydrate (P < 0.05) compared to NC. During the feeding phase of the day, FHA exhibited lower glucose (P < 0.05) and insulin (P < 0.01) levels than NC, and the degree of hypoinsulinemia was directly related to relative dietary fat (r = 0.73). Although 24-h mean GH levels did not differ, the pattern of GH release in FHA was distinctly altered from that in NC. GH pulse amplitude was blunted, pulse frequency was accelerated 40% (P < 0.01), and interpulse GH concentrations were elevated 2-fold (P < 0.01) throughout the day for FHA compared to NC. This distorted pattern of GH pulses was associated with a 40% decrease (P < 0.01) in GH-binding protein levels. Levels of the insulin-dependent insulin-like growth factor (IGF)-binding protein-1 (IGFBP-1) were elevated (P < 0.001) during the feeding portion of the day in FHA and were inversely related to insulin (r = -0.50) and directly related to cortisol (r = 0.64) levels for FHA and NC groups together. Although levels of IGF-I and IGFBP-3 did not differ, the elevation of IGFBP-1 levels in FHA resulted in a reduced (P < 0.01) ratio of IGF-I/IGFBP-1, which may decrease the bioactivity and hypoglycemic effect of IGF-I. Twenty-four-hour mean leptin levels and the diurnal excursion of leptin in FHA did not differ from those in NC. LH pulse frequency was slowed 50% (P < 0.001) in FHA, with unaltered pulse amplitude, resulting in 45% lower (P < 0.01) 24-h mean LH levels for FHA compared to NC. LH pulse frequency for the two groups was related positively to insulin (r = 0.80) levels and the ratio of IGF-I/IGFBP-1 (r = 0.70) and negatively with cortisol (r = -0.61) and IGFBP-1 (r = -0.72) concentrations. In summary, we found evidence of subclinical eating disorders in weight-stable, nonathletic women with FHA accompanied by a severe restriction of dietary fat intake. Unbalanced nutrient intake in psychogenic FHA was associated with multiple endocrine-metabolic alterations. Among these, reduced levels of plasma glucose and serum GHBP, a decrease in the ratio of IGF-I/IGFBP-1, accelerated GH pulse frequency, and elevated interpulse GH levels are indicative of a hypometabolic state. In addition, the magnitude of glucoregulatory responses (increased cortisol secretion and decreased insulin/IGF-I action) were directly related to the degree of suppression of GnRH/LH pulse frequency. These results are remarkably similar to those seen in highly trained athletes with FHA(1). Thus, nutritional deficits may represent a common contributing factor to the development and maintenance of multiple neuroendocrine-metabolic aberrations underlying both psychogenic and exercise-related FHA.

Altered binding of serum thyroid hormone to thyroxine-binding globulin in women with functional hypothalamic amenorrhea

OBJECTIVE

To further characterize hypothyroidemia with decreased serum concentrations of total triiodothyronine and total T4 in women with functional hypothalamic amenorrhea.

DESIGN

Cohort study.

SETTING

University of California San Diego Clinical Research Center.

PATIENT(S)

8 women with functional hypothalamic amenorrhea (hypogonadotropic or normogonadotropic amenorrhea of at least 6 months duration) and 9 normal cycling women in the early follicular phase of their cycles.

INTERVENTION(S)

24-hour frequent blood sampling.

MAIN OUTCOME MEASURE(S)

Comparison of levels of thyroid hormones and binding proteins between functional hypothalamic amenorrhea and normal cycling women. Measurements of serum free T4, free triiodothyronine, total T4, total triiodothyronine, reverse triiodothyronine, thyroid-binding globulin, albumin, and prealbumin levels and determination of T4 binding and binding affinity to each of the three binding proteins.

RESULT(S)

The results confirmed reduced levels of total triiodothyronine and total T4, but revealed no significant difference in free triiodothyronine and free T4, as well as reverse triiodothyronine, levels between functional hypothalamic amenorrhea and normal cycling women. Although serum levels of thyroid hormone-binding proteins were similar between normal cycling women and functional hypothalamic amenorrhea, a significant decrease in T4 bound to thyroid-binding globulin along with a decrease in apparent affinity of thyroid-binding globulin for T4 was present in functional hypothalamic amenorrhea. No differences in prealbumin- or albumin-T4 interactions were found.

CONCLUSION(S)

In functional hypothalamic amenorrhea, a reduced thyroid-binding globulin binding affinity appears to explain the disparity between normal levels of free triiodothyronine, free T4, and binding proteins in the face of reduced levels of total triiodothyronine and total T4.

Effects of [norleucine27]growth hormone-releasing hormone (GHRH) (1-29)-NH2 administration on the immune system of aging men and women

Aging in humans is associated with the decline of functional activities of the GH-insulin-like growth factor I (IGF-I) axis and the immune system. Because lymphocytes express GH-IGF-I, as well as GHRH and their respective receptors, restoration of this axis in age-advanced individuals, by the administration of GHRH, may enhance immune cell function. This hypothesis was tested by a single blind randomized placebo-controlled trial of 5 months duration, in which healthy elderly subjects (10 women, 9 men) self-administered sc nightly placebo for 4 weeks, followed by 16 weeks of [norleucine27]GHRH (1-29)-NH2 at a dose of 10 micrograms/kg. Fasting (0800 h-0900 h) blood samples were obtained for immune studies and for measurements of serum concentrations of IGF-I and soluble interleukin (IL)-2 receptor. GH pulsatility was determined in blood samples obtained at 10-min intervals for 12 h (2000 h-0800 h). Freshly isolated peripheral lymphocytes were analyzed by flow cytometric analysis for determination of lymphocyte subsets and monocytes. Mitogen stimulation responses, natural killer cell number and cytotoxicity, basal and stimulated IL-2 secretion from cultured lymphocytes, and IL-2 and IL-2R messenger RNA expression were measured. These studies were conducted at baseline, after placebo, and during GHRH analog administration at 4 and 16 weeks. Treatment with GHRH analog resulted in a significant increase (107 and 70% in men and women, respectively) in the 12-h integrated GH secretion (P < .05) and serum IGF-I levels (28%) (P < .001) in both men and women by 4 weeks and lasted 12 weeks for IGF-I and 16 weeks for GH. Activation of the immune system occurred in both sexes within 4 weeks. A 30% increase (P < .001) in lymphocytes expressing the transferrin receptor (CD71) and in monocytes (CD14) (P < .05) occurred within 4 weeks. By 16 weeks, there was a significant increase (30%) in B cells (CD20) (P < .01), in cells expressing the T cell receptor alpha/beta (20%) (P < .01), and T cell receptor gamma/delta (40%) (P < .0001). There were no changes in the number of T cells (CD3), T cell subsets (CD4, CD8), or natural killer cell (CD57) over the treatment period. The increase in B cell number was associated with enhanced responsiveness (50%) to the B cell mitogens: pokeweed mitogen (P < .01 or better) and Staphylococus aureus cells (P < .001), and a transient increase at 4 weeks in circulating IgG (P < .0001), IgM, and IgA (P < .001). T cells were functionally activated, as evidenced by a 50% increase in responsiveness to phytohemagglutinin (P < .01 or better), 70% increase in the number of lymphocytes expressing the IL-2 receptor (IL-2R) (CD25) (P < .001), and enhanced IL-2R messenger RNA expression and basal IL-2 secretion (50%) (P < .05) at 16 weeks of treatment. Furthermore, circulating soluble IL-2 receptor rose significantly (15%) (P < .05) within 4 weeks of treatment and remained elevated for the duration of the study. There were no sex differences in the immune response to GHRH analog and no adverse effects. These results indicate that GHRH analog administration has profound immune-enhancing effects and may be of therapeutic benefit in states of compromised immune function.

Inappropriate gonadotropin secretion in polycystic ovary syndrome: influence of adiposity

In recent years, there has been uncertainty concerning the association of inappropriate gonadotropin secretion (high LH and normal FSH) and the polycystic ovary syndrome (PCOS). In the present study, we ascertained the influence of body composition on LH pulsatile parameters in 33 PCOS and 32 normal cycling (NC) women across a wide range of body mass index (BMI, 19-42 kg/m2). Twenty four-hour pulsatile parameters for serum LH (10-min sampling) and pituitary gonadotropin responses to i.v. bolus GnRH (10 micrograms) were evaluated. Fasting (0800 h) FSH and steroid hormone concentrations and 24-h mean insulin levels were determined. Insulin sensitivity (SI) was assessed by rapid i.v. glucose tolerance test in a subset of 28 PCOS and 29 NC subjects. Our results showed that BMI, an indicator of relative adiposity, had a significant negative impact on 24-h mean LH pulse amplitude (r = -0.63, P < 0.001) and the peak increment of LH in response to GnRH stimulation (r = -0.41; P = 0.02) for PCOS but not NC women. In contrast, 24-h LH pulse frequency was uniformly increased (40%) in PCOS as compared with NC women independent of BMI. In PCOS women, the blunting of pulse amplitude with increasing BMI resulted in a decline in 24-h mean LH levels (r = -0.63, P < 0.001) and the ratio of LH/FSH (r = -0.44, P = 0.02) not seen in NC. With BMI < 30 kg/m2, 24-h mean LH values for PCOS women were greater than the normal range for NC in 95% (18/19) of cases, whereas 24-h LH levels failed to discriminate PCOS from NC women in 43% (6/14) of obese (BMI > 30 kg/m2) PCOS women. Thus, the diagnostic value of LH determinations is retained for PCOS women with BMI < 30 kg/m2. For screening purposes, the mean of two LH values in samples collected at 30-min intervals was found to have a discriminatory power equal to that of the 24-h mean. These findings suggest that 1) BMI negatively influences LH pulse amplitude in PCOS women principally by an effect at the pituitary level; 2) accelerated LH pulse frequency in PCOS women is not influenced by BMI and represents a basic component of hypothalamic dysfunction in PCOS women; and 3) BMI does not influence gonadotropin secretion in normal cycling women. Thus assessments of basal LH levels and the LH/FSH ratio in hyperandrogenic anovulatory women are clinically meaningful when BMI is taken into account. Investigations to define the factor(s) that link adiposity and the attenuation of LH pulse amplitude in PCOS women would add further understanding of this complex neuroendocrine-metabolic disorder.

Expression of genes encoding corticotropin-releasing factor (CRF), type 1 CRF receptor, and CRF-binding protein and localization of the gene products in the human ovary

Recently, the presence of immunoreactive corticotropin-releasing factor (IrCRF) in the thecal-stromal cells of the human ovary and the ability of CRF to suppress estrogen production by human granulosa cells in vitro have been reported. To understand the functional role of ovarian CRF requires characterization of the human ovarian CRF system, which includes CRF, type 1 CRF receptor (CRF-R1), and the high affinity CRF-binding protein (CRF-BP). Accordingly, we have examined the ovarian CRF system and the cellular distribution of these proteins and their messenger ribonucleic acids (mRNAs) using immunohistochemistry and in situ hybridization, respectively. Normal ovaries from 10 premenopausal women undergoing hysterectomy with ovariectomy were used in the analyses. IrCRF and its mRNA were localized in thecal cells of small antral and mature follicles. A low abundance of IrCRF and mRNA was also detected in stromal cells of both stages of follicles. Expression of the gene encoding CRF was more prominent in mature follicles than in small antral follicles. CRF-R1 mRNA signal was found exclusively in thecal cells of mature follicles and moderately in small antral follicles. Granulosa cells were devoid of CRF and CRF-R1 mRNAs and proteins. The IrCRF-BP, but not its transcript, was detected in thecal cells and luman of capillary vessels of the thecal/stromal compartment of mature follicles. The absence of CRF-BP gene transcript in human ovarian follicles was confirmed by reverse transcription-PCR, indicating that the IrCRF-BP detected is not derived from the ovarian transcript and suggesting that the presence of IrCRF-BP and luman of capillary vessels in the thecal compartment originates from the peripheral circulation. Thecal cells of mature follicles, relative to those of small antral follicles, exhibited an intensive immunostaining and mRNA signal for 17 alpha-hydroxylase (P450c17) indicative of androgen biosynthesis. We conclude that the thecal compartment of the human ovary contains a CRF system endowed with CRF and CRF-R1 and the blood-derived CRF-BP. Granulosa cells are devoid of the CRF system. The parallel increases in intensity of CRF, CRF-R1, and 17 alpha-hydroxylase proteins and gene expression with follicular maturation suggest that the intraovarian CRF system may play an autocrine role in androgen biosynthesis with a downstream effect on estrogen production by the granulosa cells. The functionality of the ovarian CRF system may be conditioned by the relative presence of circulating CRF-BP by virtue of its ability to compete with CRF for the CRF receptor.

Serum leptin levels in women with polycystic ovary syndrome: the role of insulin resistance/hyperinsulinemia

Polycystic ovary syndrome (PCOS) is associated with chronic anovulation, hyperandrogenemia, insulin resistance (IR)/hyperinsulinemia, and a high incidence of obesity. Thus, PCOS serves as a useful model to assess the role of IR and chronic endogenous insulin excess on leptin levels. Thirty-three PCOS and 32 normally cycling (NC) women of similar body mass index (BMI) were studied. Insulin sensitivity (S(I)) was assessed by rapid ivGTT in a subset of 28 PCOS and 29 NC subjects; percent body fat was determined by dual-energy x-ray absorptiometry (DEXA) in 14 PCOS and 17 NC. Fasting (0800 h) and 24-h mean hourly insulin levels were 2-fold higher (P < 0.0001), and S(I) was 50% lower (P = 0.005) in PCOS than in NC, while serum androstenedione (A), testosterone (T), 17-alpha hydroxyprogesterone (17OHP), and estrone (E1) levels were elevated (P < 0.0001), and sex hormone-binding globulin (SHBG) levels were decreased (P < 0.01). Twenty-four hour LH pulse frequency, mean pulse amplitude, and mean LH levels were elevated in PCOS (P < 0.001) as compared with NC. Serum leptin levels for PCOS (24.1 +/- 2.6 ng/mL) did not differ from NC (21.5 +/- 3.5 ng/mL) and were positively correlated with BMI (r = 0.81) and percent body fat (r = 0.91) for the two groups (both P < 0.0001). Leptin levels for PCOS and NC correlated positively with fasting and 24-h mean insulin levels (r = 0.81, P < 0.0001 for both PCOS and NC) and negatively with S(I) and SHBG levels. Leptin concentrations for PCOS, but not NC, correlated positively with 24-h mean glucose levels and inversely with 24-h mean LH levels and 24-h mean LH pulse amplitude. Leptin levels were not correlated with estrogen or androgen levels for either PCOS or NC, although leptin levels were positively related to the ratios of E1/SHBG and E2/SHBG for both PCOS and NC and to the ratio of T/SHBG for PCOS only. In stepwise multivariate regression with forward selection, only 24-h mean insulin levels contributed significantly (P < 0.01) to leptin levels independent of BMI and percent body fat for both PCOS and NC. Given this relationship and the presence of 2-fold higher 24-h mean insulin levels in PCOS, the expected elevation of leptin levels in PCOS was not found. This paradox may be explained by the presence of adipocyte IR specific to PCOS, which may negate the stimulatory impact of hyperinsulinemia on leptin secretion, a proposition requiring further study.

Cellular insulin resistance in adipocytes from obese polycystic ovary syndrome subjects involves adenosine modulation of insulin sensitivity

Cellular insulin resistance in polycystic ovary syndrome (PCOS) has been shown to involve a novel postbinding defect in insulin signal transduction. To find possible mechanisms for this defect, adipocytes were isolated from age- and weight-matched obese normal cycling (NC) and PCOS subjects. Insulin sensitivity for glucose transport stimulation was impaired in PCOS adipocytes (EC50 = 290 +/- 42 pmol/L) compared to that in NC cells (93 +/- 14; P < 0.005). The lipolytic responses to isoproterenol as well as maximal suppression by insulin were similar in NC and PCOS adipocytes. However, PCOS cells were less sensitive to the antilipolytic effect of insulin (EC50 = 115 +/- 33 pmol/L) compared to NC cells (42 +/- 8; P < 0.01). Treatment of adipocytes from NC subjects with the adenosine receptor agonist N6-phenylisopropyl adenosine had no effect on either insulin responsiveness or sensitivity for glucose transport stimulation. However, N6-phenylisopropyl adenosine treatment was able to normalize insulin sensitivity in PCOS cells (EC50 = 285 +/- 47 vs. 70 +/- 15 pmol/L, before and after treatment; P < 0.05). In conclusion, our results suggest that insulin resistance in PCOS, as accessed in the adipocyte, occurs at an early step in insulin signaling that is common for glucose transport and lipolysis. In addition, this insulin resistance involves an impairment of the system by which adenosine acts to modulate insulin signal transduction.

Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and women

Attenuation of the GH and insulin-like growth factor I (IGF-I) axis in aging may be responsible for changes in body composition and metabolism. This relationship has been confirmed by studies of recombinant human GH replacement in aging men and women, but the adverse effects encountered limit its clinical utility. The use of GHRH or its analogs may be an alternative mode for restoring the GH-IGF-I axis in aging individuals. Here we report the endocrine-metabolic changes in response to a GHRH analog in age-advanced men and women. A single blind, randomized, placebo-controlled trial of 5 months duration was conducted. Ten women and 9 men between the ages of 55-71 yr self-injected placebo (saline) s.c. nightly for 4 weeks followed by 16 weeks of [Nle27]GHRH-(1-29)-NH2 at a dose of 10 microg/kg. Subjects underwent 12-h nocturnal (2000-0800 h) frequent blood sampling (10-min intervals) and 24-h urine collection at baseline, after 4 weeks of placebo injections, and after 16 weeks of GHRH analog administration. GH responses to GHRH analog and spontaneous GH pulsatility were assessed. Subjects were also monitored 2, 4, 8, and 12 weeks after commencement of GHRH analog treatment. Blood pressure, body weight, and fasting insulin and glucose levels were recorded at each visit. Serum concentrations of IGF-I, IGF binding protein-1 (IGFBP-1), IGFBP-3, GH-binding protein (GHBP), lipids, and safety laboratory tests (complete blood count and chemistry profile) were measured in fasting samples (0800-0900 h). Body composition was determined by dual energy x-ray absorptiometry scan, and skin thickness was measured at four sites, including the right and left hand and volar forearm, by Harpenden skin calipers. Insulin sensitivity was assessed by a frequently sampled i.v. glucose tolerance test. Quality of life parameters, including sleep, were evaluated through self-administered questionnaires. Nightly GHRH analog administration at 2100 h induced, within 10 min, an acute release of GH, which lasted for 2 h. The GH-releasing effect of GHRH analog was sustained during the course of the study. Compared with placebo, GHRH analog induced a significant increase in 12-h integrated nocturnal GH levels in women (P < 0.01) and men (P < 0.05). This was accompanied, within 2 weeks, by increased serum levels of IGF-I (P < 0.05) and IGFBP-3 (P < 0.001), but not IGFBP-1, which remained elevated for 12 weeks, returning toward baseline by 16 weeks in both genders. Within 4 weeks, GHBP concentrations were significantly increased (P < 0.01) in women, but not in men. Although blood pressure and body weight were unaffected, GHRH analog treatment resulted in a significant increase in skin thickness (P < 0.05) in both genders and increased lean body mass in men only (P < 0.05), with no other changes in body composition or bone mineral density in either gender. There was a trend for a positive nitrogen balance in both genders, which became significant (P = 0.03) when the data were combined. Fasting insulin and glucose levels were unaltered, but a significant increase in insulin sensitivity occurred in men (P < 0.05), but not in women. Assessment of quality of life parameters revealed a significant improvement in general well-being (P < 0.05) and libido (P < 0.01) in men, but not in women, and sleep quality was unaffected in both genders. The only adverse side-effect was transient hyperlipidemia, which resolved by the end of the study. We conclude that nightly administration of GHRH analog for 4 months in age-advanced men and women activated the somatotropic axis. Although an increase in skin thickness was found in both genders, increases in lean body mass, insulin sensitivity, general well-being, and libido occurred in men but not in women. These observations suggest that GHRH analog administration induced anabolic effects favoring men more than women. Further studies are needed to define the gender differences observed in response to GHRH analog administration.

Astrocytes cultured in vitro produce estradiol-17beta and express aromatase cytochrome P-450 (P-450 AROM) mRNA

Aromatase cytochrome P-450 (P-450AROM) is an enzyme that catalyzes the conversion of androgen to estrogen. Estrogen plays an important role in the neuronal function by promoting the formation of dendrites and may be involved in protecting the neurons in the cerebral cortex against specific pathological conditions such as Alzheimer's disease. However, the cellular origin of estrogen in the brain is not known. The present study demonstrated for the first time the production of estradiol-17beta and expression of P-450AROM mRNA in astrocytes isolated from the cerebral cortex of neonatal rats. Immunocytochemical studies using a monospecific antibody against rat P-450AROM has shown that this enzyme was localized in the cytoplasm of astrocytes. Interleukin-1 (IL-1) has been shown to stimulate the proliferation and differentiation of astrocytes and to affect the aromatase activity in non-neuronal cells such as Sertoli, Leydig, and placental cells. Treatment of astrocytes with IL-1beta induced a dose-dependent inhibition of estradiol production. This inhibitory action of IL-1beta can be reversed by the addition of anti-IL-1beta antibody. Since astrocytes are involved in the synaptic reorganization in the brain by removing cellular debris and by providing the necessary biological factors for neuronal growth, the ability of astrocytes to produce estradiol-17beta and express P-450AROM mRNA in vitro suggests a new role for these cells in protecting and supporting neurons.

Melatonin enhances cortisol levels in aged women: reversible by estrogens

The administration of melatonin increases cortisol levels in postmenopausal women. Aging and hypoestrogenism are believed to impair the regulation of the hypothalamo-pituitary-adrenal axis and may participate in the determination of this altered response. In this study the implications of hypoestrogenism were tested. Seven postmenopausal women were studied. At 08.00 hr for 2 consecutive days, each woman received randomly and in a double blind fashion a pill of placebo or melatonin (100 mg). Serum melatonin and cortisol levels were evaluated at 20 min intervals, for 48 hr. Measurements were performed in the same subjects both during no estrogen supplementation and at least two cycles of conjugated estrogens administration (0.625 mg/day). During estrogen supplementation, postmenopausal women showed slightly lower cortisol levels at lunch and early night (20.00-01.00 hr). The onset of the nocturnal melatonin rise was not modified, but that of cortisol was delayed of about 60 min (P < 0.02). The administration of melatonin elicited a marked increase in daytime cortisol levels in postmenopausal women (P < 0.02), but this stimulus completely disappeared during estrogen administration. Mean nighttime (20.00-08.00 hr) cortisol levels were not modified by daytime administration of melatonin. The present data reveal that in aged postmenopausal women, reversal of hypoestrogenism, resulting from supplemental estrogens, may improve the regulation of the hypothalamopituitary-adrenal axis.

Contemporaneous melatonin administration modifies the circadian response to nocturnal bright light stimuli

We investigated whether the contemporaneous administration of melatonin can modify circadian phase shifts induced by bright light stimuli. After a baseline evaluation, 10 women were exposed for three consecutive nights to a 4-h bright light stimulus (>3,000 lx) initiated at the time of the estimated core body temperature (BT(c)) nadir. Along with light, each woman orally received, randomly and in a double-blind fashion, placebo (n = 5) or melatonin (n = 5; 1 mg 30 min before and 0.75 mg 120 min after the start of light exposure). Daily rhythms were reevaluated at the end of treatment. Bright light phase advanced, by about 90-120 min, BT(c) (P < 0.01), cortisol (P < 0.05), and melatonin (P < 0.01) rhythms. Contemporaneous administration of melatonin antagonized the phase advances of the cortisol and BT(c) rhythms, as well as the melatonin peak and melatonin offset. The phase advance of the melatonin onset was instead enhanced (P < 0.05). Contemporaneous melatonin administration modifies the capability of light to induce circadian phase shifts.

Hypoleptinemia in women athletes: absence of a diurnal rhythm with amenorrhea

The possibility that chronic nutritional deficiency alters leptin regulation and its link to reproductive function was investigated by determining serum leptin levels during a 24-h period with controlled nutrient intake in highly trained athletes with and without menstrual cyclicity and in BMI-matched cycling sedentary controls (n = 8 per group). Our data show that 24th leptin levels were reduced equally (3-fold, P < 0.001) in both cyclic and amenorrheic athletes as compared to controls. Low leptin levels in the athletic groups were consistent with their reduction in body fat (r = 0.91, P < 0.0001) relative to BMI, but were also influenced by the presence of low insulin (r = 0.70, P < 0.001) and elevated cortisol (r = -0.65, P < 0.001) levels. A diurnal pattern of 24h leptin levels, with an approximate 50% rise (P < 0.001) from nadir (0900h) to peak (0100h), was present in normally cycling athletes and controls and was strikingly absent in amenorrheic athletes. The absolute increase in leptin levels from nadir to peak was directly related to insulin excursions in response to meals (r = 0.60, P = .002) and inversely related to the amplitude of the 24h cortisol rhythm (r = -0.70, P = .0002). These findings are consistent with a link between the functionality of adipocytes, nutritional status, and integrity of the reproductive axis in humans.

Activation of immune function by dehydroepiandrosterone (DHEA) in age-advanced men

BACKGROUND

Substantial data from animal studies have demonstrated a stimulatory effect of dehydroepiandrosterone (DHEA) on immune function. However, little is known about the effects of DHEA on the human immune system. Since aging is associated with a decline in immune function and in DHEA production, we proposed that oral administration of DHEA to elderly men would result in activation of their immune system.

METHODS

Nine healthy age-advanced men (mean age of 63 years) with low DHEA-sulfate levels participated in this study. They were treated nightly with an oral placebo for 2 weeks followed by DHEA (50 mg) for 20 weeks. Fasting (0800h-0900h) blood samples were obtained at 4- to 8-week intervals for immune function studies and hormone determinations. Freshly isolated peripheral lymphocytes were used for flow cytometric identification of lymphocyte subsets, cells expressing the IL-2 receptor (IL-2R), mitogen stimulation studies, and for determining natural killer (NK) cell number and cytotoxicity. Levels of interleukin-2 (IL-2) and IL-6 secreted from cultured lymphocytes were determined under basal and mitogen stimulated conditions. Sera were analyzed for soluble IL-2 Receptor (sIL-2R) levels, insulin-like growth factor-I (IGF-I) and IGF binding protein-I (IGFBP-I) concentrations.

RESULTS

Baseline levels of serum DHEA sulfate (DHEAS), a stable marker of circulating DHEA levels, were 2 standard deviations below young adult values and increased 3-4 fold within 2 weeks. These levels were sustained throughout the duration of DHEA administration. When compared with placebo, DHEA administration resulted in a 20% increase (p < .01) in serum IGF-I, a decreasing trend in IGFBP-I, and a 32% increase in the ratio of IGF-I/IGFBP-I (p < .01). Activation of immune function occurred within 2-20 weeks of DHEA treatment. The number of monocytes increased significantly (p < .01) after 2 (45%) and 20 (35%) weeks of treatment. The population of B cells fluctuated with increases (p < .05) at 2 (35%) and 10 (29%) weeks of treatment. B cell mitogenic response increased 62% (p < .05) by 12 weeks unaccompanied by changes in serum IgG, IgA, and IgM levels. Total T cells and T cell subsets were unaltered. However, a 40% increase (p < .05) in T cell mitogenic response, 39% increase in cells expressing the IL-2R (CD25+) (p < .05), and 20% increase in serum sIL-2R levels (p < .01) were found at 12-20 weeks of DHEA treatment, suggesting a functional activation of T lymphocytes occurred. In vitro mitogen stimulated release of IL-2 and IL-6 was enhanced 50% (p < .05) and 30% (p < .01) respectively by 20 weeks of treatment without basal secretion being affected. NK cell number showed a 22-37% increase (p < .01) by 18-20 weeks of treatment with a concomitant 45% increase (p < .01) in cytotoxicity. There were no adverse effects noted with DHEA administration.

CONCLUSION

Administration of oral DHEA at a daily dose of 50 mg to age-advanced men with low serum DHEAS levels significantly activated immune function. The mechanism(s) to account for the immunoenhancing properties of DHEA are unclear. Consideration is given to the potential role of an increase in bioavailable IGF-I, which by virtue of its mitogenic effects on immune cell function, may mediate the DHEA effects. While extended studies are required, our findings suggest potential therapeutic benefits of DHEA in immunodeficient states.

Hypoleptinemia in women athletes: absence of a diurnal rhythm with amenorrhea

The possibility that chronic nutritional deficiency alters leptin regulation and its link to reproductive function was investigated by determining serum leptin levels during a 24-h period with controlled nutrient intake in highly trained athletes with and without menstrual cyclicity and in BMI-matched cycling sedentary controls (n = 8 per group). Our data show that 24th leptin levels were reduced equally (3-fold, P < 0.001) in both cyclic and amenorrheic athletes as compared to controls. Low leptin levels in the athletic groups were consistent with their reduction in body fat (r = 0.91, P < 0.0001) relative to BMI, but were also influenced by the presence of low insulin (r = 0.70, P < 0.001) and elevated cortisol (r = -0.65, P < 0.001) levels. A diurnal pattern of 24h leptin levels, with an approximate 50% rise (P < 0.001) from nadir (0900h) to peak (0100h), was present in normally cycling athletes and controls and was strikingly absent in amenorrheic athletes. The absolute increase in leptin levels from nadir to peak was directly related to insulin excursions in response to meals (r = 0.60, P = .002) and inversely related to the amplitude of the 24h cortisol rhythm (r = -0.70, P = .0002). These findings are consistent with a link between the functionality of adipocytes, nutritional status, and integrity of the reproductive axis in humans.

Nutritional and endocrine-metabolic aberrations in amenorrheic athletes

Growing evidence suggests that menstrual disturbances in female athletes are related to the metabolic cost of high levels of energy expenditure without compensatory increases in dietary intake. However, the linkage(s) between nutritional deficits and reproductive impairments as a result of slowing of LH pulsatility has not been defined. This study was directed to simultaneously characterize nutritional intake, insulin sensitivity (by rapid iv glucose tolerance test), and 24-h dynamics of insulin/glucose, cortisol, somatotropic [GH/GH-binding protein (GHBP)/insulin-like growth factor I (IGF-I)/IGF-binding proteins (IGFBPs)], and LH axes in highly trained athletes with (cycling athletes; CA) and without (amenorrheic athletes; AA) menstrual cyclicity and in age- and body mass index-matched cycling sedentary controls (CS; n = 8/group). Although daily caloric intake did not differ among the three groups, athletes (CA and AA) consumed less fat and protein than CS. However, the restriction of fat was 50% greater (P < 0.01) in AA than CA and was accompanied by increased carbohydrate (P < 0.05) and fiber (P < 0.01) intake. Athletes, independent of menstrual status, had increased (P < 0.05) insulin sensitivity and reduced insulin levels during the feeding phase of the day. Hypoinsulinemia was more pronounced in AA (P < 0.05) than CA, extending throughout the day, and was accompanied by reduced glucose increments in response to meals (P < 0.05), not seen in CA. Levels of the insulin-dependent IGFBP-1 were markedly elevated (P < 0.001) throughout the diurnal pattern in AA, whereas in CA, a modest elevation (P < 0.001) of IGFBP-1 levels occurred only during the feeding portion of the day. IGFBP-1 levels for the three groups related inversely to 24-h insulin (r = -0.63) and directly to 24-h cortisol (r = 0.69) levels. A 70-80% augmentation (P < 0.001) of 24-h mean GH levels was seen in both groups of athletes, but with distinct pulsatile features. Although pulse amplitude was increased 60% in CA with no change in pulse number, AA displayed more frequent (P < 0.001) pulses, with an elevated (P < 0.01) baseline between pulses. The distorted pattern of GH pulses seen in AA was associated with a 35% decrease in GHBP levels, not seen in CA. Although levels of IGF-I and IGFBP-3 did not differ in either CA or AA, the 2- to 4-fold higher levels of IGFBP-1 in AA than in CA and CS resulted in a 3-fold reduced ratio of IGF-I/IGFBP-1 in AA, which may decrease the bioactivity and hypoglycemic effect of IGF-I. LH pulse frequency was progressively attenuated in the athletes, with a greater (P < 0.001) slowing in AA than CA, unaccompanied by alterations in pulse amplitude or 24-h levels. LH pulse frequency was related positively with insulin (r = 0.65) levels and the ratio of IGF-I/IGFBP-1 (r = 0.69), and negatively with cortisol (r = -0.70) and IGFBP-1 (r = -0.75) concentrations. Stepwise regression analysis suggested that negative influences associated with hypercortisolemia and elevated IGFBP-1 levels predominate in determining GnRH/LH pulsatile activity in these athletes. In sum, although neuroendocrine-metabolic adaptations to the energy cost of exercise training were evident in both groups of athletes, AA displayed alterations distinct from their cycling counterparts, with evidence of a hypometabolic state, including decreased basal body temperature and reduced levels of plasma glucose and serum GHBP, a decrease in the ratio of IGF-I/IGFBP-1, accelerated GH pulse frequency, and elevated interpulse GH levels. Thus, in AA, increased insulin sensitivity, decreased circulating insulin, and a reduced hypoglycemic effect of IGF-I together with elevated GH and cortisol concentrations may comprise a cascade of glucoregulatory adaptations to repartition metabolic fuels for conservation of protein. (ABSTRACT TRUNCATED)

Insulin, somatotropic, and luteinizing hormone axes in lean and obese women with polycystic ovary syndrome: common and distinct features

The basic tenet of this investigation was that obesity is not a prerequisite in the development of polycystic ovary syndrome (PCOS), as indicated by the fact that 50% of PCOS women are not obese. Further, obesity itself is a disease entity with the common manifestation of insulin resistance/hyperinsulinemia with PCOS. Given recent evidence that insulin and GH may have gonadotropin-augmenting effects, we have determined the common and distinguishing features of neuroendocrine-metabolic dysfunctions of lean [body mass index (BMI), < 23 kg/m2] and obese (BMI, > 30 kg/m2) women with the classical form of PCOS. Insulin sensitivity, as determined by rapid i.v. glucose tolerance testing; 24-h dynamics of insulin/glucose levels, somatotropic [GH/GH-binding protein/insulin-like growth factor I (IGF-I)/IGF-binding proteins (IGFBP)], and LH axes; and their downstream effects on ovarian steroids were simultaneously assessed in eight lean PCOS and eight obese PCOS patients and an equal number of BMI-matched normal cycling controls. Our results show that insulin sensitivity was reduced 50% (P < 0.01) in lean PCOS from that in lean controls. There was a further decrease in obese controls (P < 0.01) and a 2-fold greater reduction (P < 0.001) in obese PCOS than in obese controls, suggesting that insulin resistance (IR) is a common lesion in PCOS, and that obesity contributes an additional component to IR in obese PCOS. Consistent with the degree of IR, the manifestation of compensatory hyperinsulinemia in lean PCOS was incipient, being evident only in response to meals (P < 0.05), and became overt during the 24-h fasting/feeding phases of the day in obese control (P < 0.001) with a 2- to 3-fold greater elevation (P < 0.001) in obese PCOS. An enhanced early insulin response to glucose occurs equally in obese control (P < 0.01) and obese PCOS (P < 0.05), but not in their lean counterparts. Considering the more profound IR and the associated hyperglycemia in obese PCOS, the magnitude of the early insulin release is inadequate, suggesting that beta-cell dysfunction exists in obese PCOS. Remarkable differences in the somatotropic axis were also observed; although 24-h GH pulse frequency and levels of IGF-I and IGFBP-3 were unaltered by either PCOS or obesity, the 24-h mean GH pulse amplitude was increased by 30% (P < 0.01) in lean PCOS in the presence of normal levels of high affinity GHBP and normal GH response to GHRH. In distinct contrast, the somatotropic axis in both obese control and obese PCOS was profoundly modified, with attenuation of GH pulse amplitude (P < 0.001) and GH response to GHRH (P < 0.001), resulting in a state of hyposomatotropinism with a more than 50% reduction (P < 0.001) of 24-h mean GH levels. In addition, GHBP levels were elevated 2-fold and were correlated inversely with GH (r = -0.81) and positively with insulin (r = 0.75) concentrations. IGFBP-I levels were suppressed in both obese groups, with a 4-fold greater reduction in obese PCOS than that in obese controls. Thus, the downstream effects of hyperinsulinemia on the somatotropic axis may include up-regulation of hepatic production of GHBP, suppression of IGFBP-1 (r = 0.82) and sex hormone-binding globulin (r = -0.69) levels, and a more than 3-fold increase in ratios of IGF-I/IGFBP-1 and estradiol-testosterone/sex hormone-binding globulin, thereby increasing their bioavailabilities. In contrast, LH pulsatility was unaffected by obesity alone. An accelerated LH pulse frequency was evident in both lean and obese PCOS (P < 0.001), whereas the mean 24-h LH pulse amplitude was increased in lean (P < 0.001), but not obese, PCOS patients. These events resulted in a 3-fold increase in 24-h mean LH levels in lean PCOS and a 2-fold increase in obese PCOS. Thus, increased LH pulse frequency and augmented LH response to GnRH are characteristic of PCOS, independent of obesity, and the presence of obesity in PCOS is associated with an attenuated LH pulse amplitude, not accounted f

Circulating levels of follistatin from puberty to menopause

OBJECTIVE

To determine the changes in circulating levels of follistatin, a binding protein for activin and inhibin, through the reproductive life cycle in women.

DESIGN

An open, prospective descriptive study.

SETTING

An academic endocrine research unit.

PATIENTS

Prepubertal (n = 10), midpubertal (n = 7), and postpubertal (n = 25) (early adolescent) girls, normal cycling adult women (n = 8), postmenopausal women (n = 17), and men (n = 13) were studied.

INTERVENTIONS

Normal cycling women were given Nal-Glu GnRH antagonist for 3 days in the follicular phase of the cycle.

MAIN OUTCOME MEASURE

Serum concentrations of follistatin determined in a heterologous RIA.

RESULTS

Mean follistatin levels did not change during puberty but were higher in adult and postmenopausal women. Levels of immunoreactive follistatin in men were lower than levels found in normal cycling women and postmenopausal women. Daily immunoreactive follistatin levels during the menstrual cycle remained constant and did not change significantly after ovarian suppression with GnRH antagonist.

CONCLUSION

Because dynamic changes of serum immunoreactive follistatin do not occur during ovarian activation (puberty), suppression, and age-related ovarian failure, the increase in immunoreactive follistatin levels in adult and postmenopausal women may implicate sources of follistatin other than the ovary.

Treatment of endometriosis with the antiprogesterone mifepristone (RU486)

OBJECTIVE

To evaluate the safety and efficacy of an antiprogesterone (mifepristone, RU486; Roussel-Uclaf, Romaineville, France) on endometriosis.

DESIGN

An open, prospective clinical trial.

SETTING

The clinical practice of an academic faculty.

PATIENTS

Nine women with endometriosis were studied.

INTERVENTIONS

RU486 (50 mg/d) was administered for 6 months.

MAIN OUTCOME MEASURES

Daily symptom inventories and urinary steroid metabolites were assessed before, during, and after treatment. Blood for hormone analysis was obtained weekly for 4 weeks and monthly thereafter. The extent of endometriosis, bone mineral density, circadian rhythm of cortisol, and LH pulsatility were determined before and after treatment. Safety laboratory measurements were made before and at 1, 2, and 6 months of treatment.

RESULTS

Pelvic pain and uterine cramping improved in all patients. Endometriosis regressed by 55%. All patients exhibited endocrine features of anovulatory amenorrhea without hypoestrogenism. A rise in serum LH and T levels was observed during the first month of treatment and one patient developed an elevation of liver transaminases during the last month of treatment. All other measurements were unchanged.

CONCLUSION

RU486 appears to be effective in improving the symptoms and causing regression of endometriosis in the absence of significant side effects.

Modification of circadian body temperature rhythm during the luteal menstrual phase: role of melatonin

In women during early follicular phase (FP), the rise of melatonin at night accounts for 40% of the nocturnal core body temperature (Tc) decline. In seven normal-cycling women, the circadian rhythms of Tc and melatonin of the FP were compared with those of the luteal phase (LP). In addition, in both phases the Tc response to daytime melatonin administration was investigated. Melatonin levels were comparable during the two menstrual phases, but the nocturnal melatonin onset was delayed by 90 min in the LP (P < 0.01). This was accompanied by a delay of the nadir of the Tc circadian rhythm (P < 0.002), a 0.3 degrees C elevation (P < 0.005) of the mean 24-h value, and a 40% blunting (P < 0.002) of the amplitude. This attenuation of circadian Tc in LP women was replicated in two estrogen-treated hypogonadal women by the administration of medroxyprogesterone acetate. The daytime administration of melatonin (2.5 mg) decreased Tc during the FP (P < 0.01) but was ineffective in the LP. Present data indicate that in LP, in association with high progesterone levels, an attenuated and phase-delayed circadian Tc rhythm may, in part, be due to a reduced effect of melatonin.

Replacement of DHEA in aging men and women. Potential remedial effects

DHEA in appropriate replacement doses appears to have remedial effects with respect to its ability to induce an anabolic growth factor, increase muscle strength and lean body mass, activate immune function, and enhance quality of life in aging men and women, with no significant adverse effects. Further studies are needed to confirm and extend our current results, particularly the gender differences.

Melatonin enhances cortisol levels in aged but not young women

In spite of animal data showing an effect of melatonin in the regulation of the hypothalamus-pituitary-adrenal (HPA) axis, no effect of melatonin on cortisol has been evidenced in young men. Gender and aging are believed to influence the regulation of the HPA axis, and may thus modulate the melatonin effect on cortisol. In this study we investigated whether an effect of melatonin on cortisol can be observed in women of different age. Six young women in early follicular phase (22-32 years; EFW) and eight aged women in postmenopause (54-62 years; PMW) were studied. At 08.00 h on two consecutive days each woman received, randomly and in double-blind fashion, a pill of placebo or melatonin (100 mg). Serum levels of melatonin and cortisol were evaluated at 20-min intervals for 48 h. In comparison to EFW, PMW showed an earlier onset of nocturnal melatonin (p < 0.05) and cortisol rise (p < 0.01) and higher cortisol levels at lunch (p < 0.05) and early evening (p < 0.01). Melatonin administration did not modify serum cortisol levels in EFW but elicited a marked increase of daytime cortisol levels in PMW (p < 0.02). The present data reveal that in aged PMW the cortisol levels are enhanced at selected circadian times and are stimulated by melatonin.

Metabolic features of polycystic ovary syndrome are found in adolescent girls with hyperandrogenism

Recently, we reported that hyperandrogenism in adolescent girls is accompanied by augmented LH pulsatility and elevated LH/FSH ratio with increased ovarian volume. Together with higher concentrations of 17-hydroxyprogesterone, androstenedione, testosterone, and estrone that are ovarian in origin, these neuroendocrine features are identical to those seen in adult women with polycystic ovary syndrome. In the present study, we report the metabolic characteristics of these hyperandrogenic adolescent girls. The GH insulin-like growth factor I (IGF-I)-binding protein (BP)-3 axis, insulin sensitivity, and insulin-IGFBP-1/insulin sex hormone binding globulin axes were evaluated in 13 adolescent girls (ages 11-18 yr) with mild to moderate signs of hyperandrogenism (HA) and 28 age-matched normal girls. Insulin sensitivity was assessed by a frequent-sample iv glucose tolerance test (ivGTT, 0.3 g/kg). Twenty-four hour blood samples were obtained at 10-min intervals and were used to determine GH pulsatility (20-min samples), IGFBP-3 levels (0800-0900 h), and fluctuations of insulin, IGFBP-1, and IGF-I (hourly samples) during feeding and fasting phases of the day. In addition, GH responses to GHRH stimulation (1 microgram/kg) were assessed. Fasting insulin concentrations, but not plasma glucose levels, were significantly elevated in the HA group compared with those in the normal group (256 +/- 35 vs. 103 +/- 24 pmol/L, P = 0.0008), as were insulin responses to ivGTT and meals (P < 0.01) and 24-h mean insulin concentrations (P < 0.01). Thus, hyperinsulinemia with normal fasting glucose levels in HA girls may reflect insulin resistance, as suggested by the increased ratio of insulin and glucose (P < 0.001). All measures of insulin were correlated with body mass index (BMI); however, insulin remained significantly higher in the HA group after correcting for BMI, suggesting that decreased insulin sensitivity was related to other factors in addition to BMI. Twenty-four hour IGFBP-1 concentrations showed a diurnal pattern with an inverse relationship to insulin, and 24-h mean concentrations were lower in the HA group (0.35 +/- 0.13 vs. 0.76 +/- 0.09 micrograms/L, P = 0.02). Reduced sex hormone binding globulin levels were also inversely related to insulin levels (P = 0.0007). In contrast, GH pulsatile characteristics and IGF-I/IGFBP-3 levels, as well as GH responses to GHRH, were similar between the groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Modulation of anterior pituitary luteinizing hormone response to gonadotropin-releasing hormone by insulin-like growth factor I in vitro

OBJECTIVE

To investigate how much insulin-like growth factor I may modulate the LH response to GnRH.

DESIGN

In primary cultures of male rat anterior pituitary cells, the LH response to GnRH (10(-9) M) was evaluated after a 24-hour preincubation with medium alone, IGF-I (1, 5, 10, 15 nM), polyclonal antibody anti-IGF-I (Ab-anti-IGF-I), (1:3,000; 1:10,000), or rabbit serum (1:3,000; 1:10,000) as control.

MAIN OUTCOME MEASURE

Gonadotropin-releasing hormone-induced LH release from primary cultures of male rat anterior pituitary cells.

RESULTS

Insulin-like growth factor I induces a dose-dependent stimulus on the LH response to GnRH. Insulin-like growth factor I at doses of 10 and 15 nM exerted a maximal stimulus, increasing the LH response to GnRH by 30%. The Ab-anti-IGF-I at both dilutions reduced the LH response to GnRH by 30%. No effect was exerted by rabbit serum.

CONCLUSIONS

Present data indicate that IGF-I may enhance the normal LH response to GnRH from rat anterior pituitary glands, suggesting important influences of this growth factor in the modulation of anterior pituitary LH release.

Regression of uterine leiomyomata to the antiprogesterone RU486: dose-response effect

OBJECTIVE

To study the response of uterine leiomyomata to three daily doses of RU486 (5, 25, and 50 mg).

DESIGN

Prospective nonrandomized trial of women with symptomatic leiomyomata.

SETTING

Patients from the clinical practice of the authors at the University of California, San Diego Medical Center.

PATIENTS

Ten patients with symptomatic leiomyomata previously reported after treatment with 50 mg of RU486 daily for 3 months. Eleven patients treated with 25 mg of RU486 daily and nine patients placed on 5 mg of RU486 daily for 12 weeks.

MAIN OUTCOME MEASURES

Changes in leiomyomata volume as measured with vaginal ultrasounds at baseline and monthly thereafter. Frequent blood samples for hematology, chemistry, and hormone levels were obtained. Twenty-four-hour urine collections for free cortisol and creatinine were obtained at baseline and at 12 weeks.

RESULTS

All three doses induce ovarian acyclicity. Administration of 50 mg of RU486 decreases leiomyomata volume to 78.1% +/- 4.8% of baseline at 4 weeks, 60.5% +/- 6.6% at 8 weeks, and 51.0% +/- 9.2% after 12 weeks of treatment. Regressive response in patients treated with 25 mg of RU486 daily was 76.3% +/- 5.0% of baseline at 4 weeks, 54.0% +/- 5.1% at 8 weeks, and 44.0% +/- 5.0% after 12 weeks. At 5 mg of RU486 leiomyomata volume was 80.6% +/- 8.3% of baseline after 4 weeks, 63.7% +/- 14.6% after 8 weeks, and 74.4% +/- 19.8% after 12 weeks of therapy.

CONCLUSIONS

Although acyclicity is seen at all three doses, an effective dose to cause a clinically significant (50%) decrease in leiomyomata volume appears to be 25 mg daily.

Clomiphene citrate reduces serum insulin-like growth factor I and increases sex hormone-binding globulin levels in women with polycystic ovary syndrome

OBJECTIVES

To evaluate the effect of clomiphene citrate (CC) on circulating levels of insulin-like growth factor I (IGF-I) and sex hormone-binding globulin (SHBG) in patients with polycystic ovary syndrome (PCOS).

DESIGN

Prospective open trial.

PATIENTS

Eight women with clinical and biochemical evidence of PCOS.

INTERVENTION

One hundred fifty milligrams CC was administered orally for 5 days.

MAIN OUTCOME MEASURES

Serum IGF-I, SHBG, LH, FSH, and E2 levels were determined for 8 days, beginning 3 days before CC treatment.

RESULTS

A progressive decline in serum IGF-I levels was observed in all subjects reaching a maximum of 30% on the 5th day of therapy (40.6 +/- 5.1 to 28.7 +/- 4.0 nmol/L [conversion factor to SI unit, 0.13]). This was correlated inversely with the expected rises in LH, FSH, and E2 levels. Concomitantly, there was a 23% rise in SHBG levels. The absolute decrease of IGF-I levels was negatively correlated with age and was independent of body mass index.

CONCLUSIONS

These observations suggest that oral administration of CC has an impact on the IGF-I and SHBG systems, which may be involved in the initiation of ovulatory function in PCOS.

Exogenous melatonin enhances luteinizing hormone levels of women in the follicular but not in the luteal menstrual phase

OBJECTIVE

To investigate the effect of exogenous melatonin on LH pulsatility in women during the follicular and luteal menstrual phases.

DESIGN

Randomized, double-blind placebo-controlled study.

PATIENTS

Normal cycling young women (25 to 35 years old).

INTERVENTIONS

Each subject was admitted at the Clinical Research Center for 2 consecutive days on both the follicular and the luteal menstrual phases. On each day, at 7:00 A.M. an indwelling catether was placed in an antecubital vein for a 10 minutes blood sampling from 9:00 A.M. to 5:00 P.M. On the 2 consecutive days of both the follicular and the luteal menstrual phases, each subject randomly received either placebo or melatonin pills (1 mg at 8:00 and 0.75 mg at 10:00 and 12:00 A.M.).

MAIN OUTCOME MEASURE

Luteinizing hormone pulsatility.

RESULTS

The amplitude of LH pulses and mean LH levels were increased by melatonin in the follicular but not in the luteal menstrual phase.

CONCLUSIONS

The stimulatory effect of exogenous melatonin on LH is modulated by the endocrine environment and selectively exerted in the follicular phase of the menstrual cycle.

Endometrial effects of long-term low-dose administration of RU486

OBJECTIVE

To examine endometrial response to long-term low-does RU486 administration.

DESIGN

Retrospective controlled study of women with endometriosis treated for 6 months with 50 mg RU486 daily for 6 months. Controls consisted of women in the follicular phase of a spontaneous cycle undergoing endometrial biopsy.

SETTING

Patients from the clinical practice of the authors at the University of California, San Diego Medical Center.

PATIENTS AND INTERVENTIONS

Nine patients treated with long-term low-dose RU486 and nine normal cycling controls undergoing hysterectomy or endometrial biopsy for benign disease.

MAIN OUTCOME MEASURES

Changes in endometrial morphology and immunohistochemical analysis for estrogen receptor (ER) and progesterone receptor (PR) protein.

RESULTS

All patients treated with RU486 exhibited abnormal endometrial morphology. The endometrial glands were irregular in size and shape. The stroma was varied but consisted predominantly of dense cellular stroma with frequent mitotic figures. The glands were lined by a combination of epithelial types some of which were secretory. No cytologic atypia was seen. Levels of ER immunoreactivity, as determined by image analysis, were greater in the stroma with no difference in PR immunoreactivity compared with controls. No difference in ER and PR immunoreactivity were seen in the glands compared with normal controls.

CONCLUSION

The generalized cystic changes demonstrated are consistent with a chronic unopposed estrogen effect and are concordant with hormonal data showing early to midfollicular phase levels of estrogens. They also are consistent with our findings of increased ER immunoreactivity in the stroma. Evidence of minimal P agonist effect was noted.

Expression of human gonadotropin-releasing hormone receptor gene in the placenta and its functional relationship to human chorionic gonadotropin secretion

Placental GnRH is one of the potential paracrine regulators of hCG secretion from the trophoblasts during pregnancy. Maternal serum hCG levels exhibit an exponential rise during the first 6 weeks of pregnancy, peak at 9-10 weeks, decline to a nadir at 20 weeks, and remain at low levels during the rest of pregnancy. However, the placental content of GnRH does not parallel the time course of hCG secretion, and GnRH messenger ribonucleic acid (mRNA) levels in the placenta remain unchanged during pregnancy. These data do not conform with a simple paracrine mechanism of GnRH as a regulator of hCG secretion. We, therefore, examined the potential variation in GnRH receptor gene expression in the placenta, which may account for the GnRH-mediated dynamic pattern of hCG secretion during gestation. First, we established a functional relationship of GnRH and hCG secretion. Using a placental explant culture system, a dose-response effect of hCG secretion was observed in the placental explant at 9 weeks when treated with GnRH ranging from 10(-9)-10(-7) mol/L. The effect of GnRH was completely blocked by a GnRH antagonist (Nal-Glu). The relative responsiveness of hCG secretion to GnRH stimulation at 10(-7) mol/L was further evaluated in placental explants at 6, 9, and 40 weeks gestation. Whereas the 9-week placenta showed a maximal response (> 300%) relative to the 6-week placenta, there was no response in term placenta. Again, the effects of GnRH on hCG secretion were blocked by Nal-Glu, supporting a receptor-mediated event. Localization of mRNA encoding human GnRH receptor in human placenta at 6, 9, 12, 20, and 40 weeks gestation was established by in situ hybridization. The mRNA signals were present in both cytotrophoblast and syncytiotrophoblast cell layers. Signal intensities varied with gestational ages and were abundant at 6 weeks, peaked at 9 weeks, declined at 12 and 20 weeks, and were undetectable at term. The present study demonstrates, for the first time, that GnRH receptor mRNA is expressed in both cytotrophoblasts and syncytiotrophoblasts and exhibits changes paralleling the time course of hCG secretion during pregnancy. These data provide a mechanistic understanding that the paracrine/autocrine regulation of hCG secretion by placental GnRH is mediated through an increase followed by a decline in GnRH receptor gene expression from the first trimester to term placenta.

Hypothermic effect of melatonin and nocturnal core body temperature decline are reduced in aged women

In young humans, the nocturnal rise of the hypothermic hormone melatonin generates 40-50% of the circadian core body temperature (Tc) decline. The nocturnal Tc decline is reduced with aging in men. In this study we investigated whether a similar attenuation occurs in women and whether it is associated with a reduced serum concentration and/or action of melatonin. The circadian rhythms of melatonin and Tc (measured in the vagina) and the responses of both Tc (measured into the auricolar canal) and finger skin temperature to melatonin administration (100 mg at 0800) were investigated in two experiments involving young (22-32 yr) and aged (54-62 yr) women. In aged women, the nocturnal onset of the melatonin rise was phase advanced and Tc decline and Tc rhythm amplitude were reduced (P < 0.0005). The serum melatonin concentrations in aged women were similar to those of young women, but the melatonin capability to reduce Tc and increase skin temperature was markedly impaired. Our data show that, in women, an aging-associated reduction of temperature responses to melatonin is probably involved in inducing an attenuation of the nocturnal Tc decline and circadian Tc rhythm amplitude.

Persistence of premenstrual syndrome during low-dose administration of the progesterone antagonist RU 486

OBJECTIVE

To test whether progesterone or progesterone receptors are important mediators of premenstrual syndrome (PMS) and whether progesterone antagonist RU 486 would alleviate symptoms.

METHODS

Following extensive screening including physical and psychological assessment, seven women with severe PMS participated in a 6-month, randomized, double-blind, placebo-controlled, crossover study. The treatment included 3 months of low-dose RU 486 (5 mg alternate days for four doses, beginning 3 days after the urinary LH surge) or placebo, administered in a similar fashion. Symptoms were evaluated using the Calendar of Premenstrual Experiences, Beck Depression Inventory, State-Trait Anxiety Inventory, and the Profile of Mood States.

RESULTS

Symptoms of PMS were similar during RU 486 and placebo treatments.

CONCLUSION

Luteal-phase administration of low-dose RU 486 does not significantly reduce the physical or behavioral manifestations of PMS.