Bone marrow adipose tissue is associated with fracture history in anorexia nervosa.

Although bone mineral density (BMD) is decreased and fracture risk increased in anorexia nervosa, BMD does not predict fracture history in this disorder. We assessed BMD, bone microarchitecture, and bone marrow adipose tissue (BMAT) in women with anorexia nervosa and found that only BMAT was associated with fracture history. INTRODUCTION: Anorexia nervosa (AN) is a psychiatric disorder characterized by low body weight, low BMD, and increased risk of fracture. Although BMD is reduced and fracture risk elevated, BMD as assessed by DXA does not distinguish between individuals with versus those without prior history of fracture in AN. Despite having decreased peripheral adipose tissue stores, individuals with AN have enhanced bone marrow adipose tissue (BMAT), which is inversely associated with BMD. Whether increased BMAT is associated with fracture in AN is not known. METHODS: We conducted a cross-sectional study in 62 premenopausal women, including 34 with AN and 28 normal-weight women of similar age. Fracture history was collected during patient interviews and BMD measured by DXA, BMAT by 1H-MRS, and parameters of bone microarchitecture by HR-pQCT. RESULTS: Sixteen women (47.1%) with AN reported prior history of fracture compared to 11 normal-weight women (39.3%, p = 0.54). In the entire group and also the subset of women with AN, there were no significant differences in BMD or parameters of bone microarchitecture in women with prior fracture versus those without. In contrast, women with AN with prior fracture had greater BMAT at the spine and femur compared to those without (p = 0.01 for both). CONCLUSION: In contrast to BMD and parameters of bone microarchitecture, BMAT is able to distinguish between women with AN with prior fracture compared to those without. Prospective studies will be necessary to understand BMAT's potential pathophysiologic role in the increased fracture risk in AN.

IGF-1 is associated with estimated bone strength in anorexia nervosa.

IGF-1 and leptin are two nutritionally dependent hormones associated with low bone mass in women with anorexia nervosa. Using finite element analysis, we estimated bone strength in women with anorexia nervosa and found that IGF-1 but not leptin correlated significantly with estimated bone strength in both the radius and tibia. PURPOSE: Women with anorexia nervosa, a psychiatric disorder characterized by self-induced starvation and low body weight, have impaired bone formation, low bone mass, and an increased risk of fracture. IGF-1 and leptin are two nutritionally dependent hormones that have been associated with low bone mass in women with anorexia nervosa. We hypothesized that IGF-1 and leptin would also be positively associated with estimated bone strength in women with anorexia nervosa. METHODS: In this cross-sectional study of 38 women (19 with anorexia nervosa and 19 normal-weight controls), we measured serum IGF-1 and leptin and performed finite element analysis of high-resolution peripheral quantitative CT images to measure stiffness and failure load of the distal radius and tibia. RESULTS: IGF-1 was strongly correlated with estimated bone strength in the radius (R = 0.52, p = 0.02 for both stiffness and failure load) and tibia (R = 0.55, p = 0.01 for stiffness and R = 0.58, p = 0.01 for failure load) in the women with anorexia nervosa but not in normal-weight controls. In contrast, leptin was not associated with estimated bone strength in the group of women with anorexia nervosa or normal-weight controls. CONCLUSIONS: IGF-1 is strongly associated with estimated bone strength in the radius and tibia in women with anorexia nervosa. Further studies are needed to assess whether treatment with recombinant human IGF-1 will further improve bone strength and reduce fracture risk in this population.

A consensus on the diagnosis and treatment of acromegaly complications.

In March 2011, the Acromegaly Consensus Group met to revise and update the guidelines on the diagnosis and treatment of acromegaly complications. The meeting was sponsored by the Pituitary Society and the European Neuroendocrinology Association and included experts skilled in the management of acromegaly. Complications considered included cardiovascular, endocrine and metabolic, sleep apnea, bone diseases, and mortality. Outcomes in selected, related clinical conditions were also considered, and included pregnancy, familial acromegaly and invasive macroadenomas. The need for a new disease staging model was considered, and design of such a tool was proposed.

Effects of growth hormone deficiency on body composition and biomarkers of cardiovascular risk after definitive therapy for acromegaly.

BACKGROUND: Both growth hormone (GH) excess and GH deficiency are associated with abnormalities in body composition and biomarkers of cardiovascular risk in patients with pituitary disorders. However, the effects of developing GH deficiency after definitive treatment of acromegaly are largely unknown. OBJECTIVE: To determine whether development of GH deficiency after definitive therapy for acromegaly is associated with increased visceral adiposity and biomarkers of cardiovascular risk compared with GH sufficiency after definitive therapy for acromegaly. DESIGN: Cross-sectional. PATIENTS: We studied three groups of subjects, all with a history of acromegaly (n = 76): subjects with subsequent GH deficiency (GHD; n = 31), subjects with subsequent GH sufficiency (GHS; n = 25) and subjects with active acromegaly (AA; n = 20). No study subjects were receiving somatostatin analogues, dopamine agonists or hGH. MEASUREMENTS: Body composition (by DXA), abdominal adipose tissue depots (by cross-sectional CT), total body water (by bioimpedance analysis) and carotid intima-media thickness (IMT) were measured. Fasting morning serum was collected for high-sensitivity C-reactive protein (hsCRP), lipids and lipoprotein levels. An oral glucose tolerance test was performed, and homoeostasis model of assessment-insulin resistance (HOMA-IR) was calculated. RESULTS: Abdominal visceral adipose tissue, total adipose tissue and total body fat were higher in subjects with GHD than GHS or AA (P < 0·05). Subcutaneous abdominal fat was higher, and fibrinogen and IMT were lower in GHD (but not GHS) than AA (P < 0·05). Patients with GHD had the highest hsCRP, followed by GHS, and hsCRP was lowest in AA (P < 0·05). Fasting glucose, 120-min glucose, fasting insulin, HOMA-IR and per cent total body water were lower in GHD and GHS than AA (P < 0·05). Triglycerides were higher in GHS than AA (P < 0·05). Lean body mass, mean arterial pressure, total cholesterol, HDL and LDL were comparable among groups. CONCLUSIONS: Development of GHD after definitive treatment of acromegaly may adversely affect body composition and inflammatory biomarkers of cardiovascular risk but does not appear to adversely affect glucose homoeostasis, lipids and lipoproteins, or other cardiovascular risk markers.

Current management practices for acromegaly: an international survey.

To determine whether peer-reviewed consensus statements have changed clinical practice, we surveyed acromegaly care in specialist centers across the globe, and determined the degree of adherence to published consensus guidelines on acromegaly management. Sixty-five acromegaly experts who participated in the 7th Acromegaly Consensus Workshop in March 2009 responded. Results indicated that the most common referring sources for acromegaly patients were other endocrinologists (in 26% of centers), neurosurgeons (25%) and primary care physicians (21%). In sixty-nine percent of patients, biochemical diagnoses were made by evaluating results of a combination of growth hormone (GH) nadir/basal GH and elevated insulin like growth factor-I (IGF-I) levels. In both Europe and the USA, neurosurgery was the treatment of choice for GH-secreting microadenomas and for macroadenomas with compromised visual function. The most widely used criteria for neurosurgical outcome assessment were combined measurements of IGF-I and GH levels after oral glucose tolerance test (OGTT) 3 months after surgery. Ninety-eight percent of respondents stated that primary treatment with somatostatin receptor ligands (SRLs) was indicated at least sometime during the management of acromegaly patients. In nearly all centers (96%), the use of pegvisomant monotherapy was restricted to patients who had failed to achieve biochemical control with SRL therapy. The observation that most centers followed consensus statement recommendations encourages the future utility of these workshops aimed to create uniform management standards for acromegaly.

Bone metabolism in adolescents with anorexia nervosa.

Adolescents with anorexia nervosa (AN) are at risk for low bone mass at multiple sites, associated with decreased bone turnover. Bone microarchitecture is also affected, with a decrease in bone trabecular volume and trabecular thickness, and an increase in trabecular separation. The adolescent years are typically the time when marked increases occur in bone mass accrual towards the attainment of peak bone mass, an important determinant of bone health and fracture risk in later life. AN often begins in the adolescent years, and decreased rates of bone mass accrual at this critical time are therefore also concerning for deficits in peak bone mass. Factors contributing to low bone density and decreased rates of bone accrual include alterations in body composition such as low body mass index and lean body mass, and hormonal alterations such as hypogonadism, a nutritionally acquired resistance to GH and low levels of IGF-I, relative hypercortisolemia, low levels of leptin, and increased adiponectin (for fat mass) and peptide YY. Therapeutic strategies include optimizing weight and menstrual recovery, and adequate calcium and vitamin D replacement. Oral estrogen-progesterone combination pills are not effective in increasing bone density in adolescents with AN. Recombinant human IGF-I increases levels of bone formation markers in the short term, while long-term effects remain to be determined. Bisphosphonates act by decreasing bone resorption, and are not optimal for use in adolescents with AN, in whom the primary defect is low bone formation.

Comparison of pegvisomant and long-acting octreotide in patients with acromegaly naïve to radiation and medical therapy.

BACKGROUND: Normalization of IGF-I in patients with acromegaly is associated with a decrease in mortality. Pegvisomant may be more effective in lowering IGF-I than octreotide. SUBJECTS AND METHODS: The efficacy and safety of pegvisomant and octreotide long-acting release (LAR) were compared in 118 patients with acromegaly in this 52-week, multicenter, open-label, randomized study. The primary endpoint was IGF-I normalization at week 52. Secondary endpoints included mean changes from baseline in IGF-I, IGF binding protein 3, acromegaly signs and symptom scores, ring size, acromegaly quality of life questionnaire scores, and safety. RESULTS: Fifty-six patients received pegvisomant and 57 received octreotide LAR. IGF-I normalized in 51% of pegvisomant patients and 34% treated with octreotide LAR (p=0.09, ns). Patients with baseline IGF-I > or = 2x upper limit of normal had a higher rate of IGF-I normalization with pegvisomant vs octreotide LAR (p=0.05). Among the patients who did not achieve a normalized IGF-I, pegvisomant-treated patients were more likely to be receiving < 30 mg of study drug (71% vs 16%). Treatment-related adverse events were mild-to-moderate in both groups. Mean fasting glucose decreased in diabetic and non-diabetic patients on pegvisomant whereas octreotide LAR was associated with an increase at week 52 (p=0.005 and p=0.003 between groups, respectively). Mean change in tumor volume during treatment was similar between groups. CONCLUSIONS: Pegvisomant and octreotide LAR were equally effective in normalizing IGF-I in the overall population, and pegvisomant was more effective in patients with higher baseline IGF-I levels. Pegvisomant had a more favorable effect on parameters of glycemic control.

Treatment of adrenocorticotropin-dependent Cushing's syndrome: a consensus statement.

OBJECTIVE: Our objective was to evaluate the published literature and reach a consensus on the treatment of patients with ACTH-dependent Cushing's syndrome, because there is no recent consensus on the management of this rare disorder. PARTICIPANTS: Thirty-two leading endocrinologists, clinicians, and neurosurgeons with specific expertise in the management of ACTH-dependent Cushing's syndrome representing nine countries were chosen to address 1) criteria for cure and remission of this disorder, 2) surgical treatment of Cushing's disease, 3) therapeutic options in the event of persistent disease after transsphenoidal surgery, 4) medical therapy of Cushing's disease, and 5) management of ectopic ACTH syndrome, Nelson's syndrome, and special patient populations. EVIDENCE: Participants presented published scientific data, which formed the basis of the recommendations. Opinion shared by a majority of experts was used where strong evidence was lacking. CONSENSUS PROCESS: Participants met for 2 d, during which there were four chaired sessions of presentations, followed by general discussion where a consensus was reached. The consensus statement was prepared by a steering committee and was then reviewed by all authors, with suggestions incorporated if agreed upon by the majority. CONCLUSIONS: ACTH-dependent Cushing's syndrome is a heterogeneous disorder requiring a multidisciplinary and individualized approach to patient management. Generally, the treatment of choice for ACTH-dependent Cushing's syndrome is curative surgery with selective pituitary or ectopic corticotroph tumor resection. Second-line treatments include more radical surgery, radiation therapy (for Cushing's disease), medical therapy, and bilateral adrenalectomy. Because of the significant morbidity of Cushing's syndrome, early diagnosis and prompt therapy are warranted.

Effects of testosterone therapy on cardiovascular risk markers in androgen-deficient women with hypopituitarism.

CONTEXT: Low-dose testosterone replacement therapy in women with relative androgen deficiency has been shown to have beneficial effects on body composition, bone mass, and psychosexual function. However, the safety of chronic testosterone administration on cardiovascular risk and insulin resistance is unknown. OBJECTIVE: The aim of the study was to determine the effects of physiological testosterone replacement on cardiovascular risk markers and insulin resistance in women. DESIGN: A 12-month, randomized, placebo-controlled study was conducted. SETTING: A General Clinical Research Center was the setting for the study. STUDY PARTICIPANTS: A total of 51 women of reproductive age with androgen deficiency due to hypopituitarism participated. INTERVENTION: Study participants were randomized to physiological testosterone administration, 300 mug daily, or placebo, by patch. MAIN OUTCOME MEASURES: We measured fasting glucose, fasting insulin, insulin-resistance homeostasis model of assessment (IRHOMA), quantitative insulin sensitivity check index (QUICKI), high-sensitivity C-reactive protein, vascular cell adhesion molecule (VCAM), leptin, lipoprotein (a), apolipoprotein A1, and homocysteine. RESULTS: At 12 months, fasting insulin and IRHOMA were significantly lower in the testosterone compared with the placebo group, and there was a trend toward a higher QUICKI level at 12 months in the testosterone compared with the placebo group. These differences were no longer significant after controlling for baseline levels. We observed no effect, either positive or negative, of testosterone administration on high-sensitivity C-reactive protein, VCAM leptin, lipoprotein (a), or apolipoprotein A1. CONCLUSIONS: Our data suggest that physiological testosterone replacement in women with hypopituitarism for 12 months does not increase, and may improve, insulin resistance. Chronic low-dose testosterone administration does not increase markers of cardiovascular disease reflecting several different mechanistic pathways. Large, randomized, placebo-controlled, long-term prospective studies are needed to determine whether low-dose testosterone replacement affects cardiovascular risk and event rates in women.

Androgens in women with anorexia nervosa and normal-weight women with hypothalamic amenorrhea.

CONTEXT: Anorexia nervosa and normal-weight hypothalamic amenorrhea are characterized by hypogonadism and hypercortisolemia. However, it is not known whether these endocrine abnormalities result in reductions in adrenal and/ or ovarian androgens or androgen precursors in such women, nor is it known whether relative androgen deficiency contributes to abnormalities in bone density and body composition in this population. OBJECTIVE: Our objective was to determine whether endogenous androgen and dehydroepiandrosterone sulfate (DHEAS) levels: 1) are reduced in women with anorexia nervosa and normal-weight hypothalamic amenorrhea, 2) are reduced further by oral contraceptives in women with anorexia nervosa, and 3) are predictors of weight, body composition, or bone density in such women. DESIGN AND SETTING: We conducted a cross-sectional study at a general clinical research center. STUDY PARTICIPANTS: A total of 217 women were studied: 137 women with anorexia nervosa not receiving oral contraceptives, 32 women with anorexia nervosa receiving oral contraceptives, 21 normal-weight women with hypothalamic amenorrhea, and 27 healthy eumenorrheic controls. MAIN OUTCOME MEASURES: Testosterone, free testosterone, DHEAS, bone density, fat-free mass, and fat mass were assessed. RESULTS: Endogenous total and free testosterone, but not DHEAS, were lower in women with anorexia nervosa than in controls. More marked reductions in both free testosterone and DHEAS were observed in women with anorexia nervosa receiving oral contraceptives. In contrast, normal-weight women with hypothalamic amenorrhea had normal androgen and DHEAS levels. Lower free testosterone, total testosterone, and DHEAS levels predicted lower bone density at most skeletal sites measured, and free testosterone was positively associated with fat-free mass. CONCLUSIONS: Androgen levels are low, appear to be even further reduced by oral contraceptive use, and are predictors of bone density and fat-free mass in women with anorexia nervosa. Interventional studies are needed to confirm these findings and determine whether oral contraceptive use, mediated by reductions in endogenous androgen levels, is deleterious to skeletal health in such women.

Gonadotropin-releasing hormone receptor mRNA expression by human pituitary tumors in vitro.

An important question in the pathogenesis and regulation of human gonadotroph adenomas is whether heterogeneous gonadotropin responses to gonadotropin-releasing hormone (GnRH) are due to dysregulation of GnRH receptor biosynthesis and/or cell-signaling pathways. We investigated gonadotropin responsiveness to pulsatile GnRH in 13 gonadotroph adenomas. All tumors had evidence of follicle-stimulating hormone (FSH) beta and alpha subunit biosynthesis using reverse transcriptase/polymerase chain reaction (RTPCR) techniques. Four tumors significantly increased gonadotropin and/or free subunit secretion during pulsatile 10(-8) M GnRH administration. The GnRH antagonist Antide (10(-6) to 10(-8) M) blocked secretory increases in all GnRH-responsive tumors. Gonadotropin and/or free subunit secretion increased after 60 mM KCl, confirming that GnRH nonresponsiveness was not due to intracellular gonadotropin depletion. We hypothesized that GnRH nonresponsiveness in these tumors may be due to GnRH receptor (GnRH-Rc) biosynthetic defects. RTPCR analyses detected GnRH-Rc transcripts only in responsive tumors and normal human pituitary. This is the first demonstration of a cell-surface receptor biosynthetic defect in human pituitary tumors. We conclude (a) one third of gonadotroph tumors respond to pulsatile GnRH in vitro, (b) GnRH-Rc mRNA is detected in human gonadotroph adenomas and predicts GnRH responsiveness, and (c) GnRH-Rc biosynthetic defects may underlie GnRH nonresponsiveness in gonadotroph tumors.

Effects of rhIGF-I administration on bone turnover during short-term fasting.

Insulin-like growth factor-I (IGF-I) is a nutritionally dependent bone trophic hormone which stimulates osteoblast function and collagen synthesis in vivo and in vitro. We hypothesized that in the fasting state, IGF-I levels would decline significantly and would establish a model in which we could investigate the effects of IGF-I administration on bone turnover. We therefore studied 14 normal women ages 19-33 (mean, 24 +/- 4 [SD] years) during a complete 10-d fast. After 4 d of fasting, subjects were randomized to receive rhIGF-I or placebo subcutaneously twice a day for 6 d. Bone turnover was assessed using specific markers of formation (osteocalcin and type I procollagen carboxyl-terminal propeptide [PICP]) and resorption (pyridinoline, deoxypyridinoline, type I collagen crosslinked N-telopeptide [N-telopeptide] and hydroxyproline). Serum levels of PICP and osteocalcin decreased from 143 +/- 52 to 60 +/- 28 ng/ml (P = 0.001) and from 7.6 +/- 5.4 to 4.2 +/- 3.1 ng/ml (P = 0.001) respectively with 4 d of fasting. Urinary excretion of pyridinoline and deoxypyridinoline decreased from 96 +/- 63 to 47 +/- 38 nmol/mmol creatinine (P < 0.05) and from 28 +/- 17 to 14 +/- 11 nmol/mmol creatinine (P < 0.05) respectively. Mean IGF-I levels decreased from 310 +/- 81 to 186 +/- 78 ng/ml (P = 0.001). In the second part of the experimental protocol, serum osteocalcin and PICP levels increased 5- and 3-fold, respectively with rhIGF-I administration and were significantly elevated compared with the placebo group at the end of treatment (20.9 +/- 17.3 vs. 5.9 +/- 6.4 ng/ml for osteocalcin [P < 0.05] and 188 +/- 45 vs. 110 +/- 37 ng/ml for PICP [P < 0.05]). In contrast, all four markers of bone resorption, including urinary pyridinoline, deoxypyridinoline, N-telopeptide and hydroxyproline were unchanged with rhIGF-I administration. This report is the first to demonstrate that bone turnover falls rapidly with acute caloric deprivation in normal women. RhIGF-I administration uncouples bone formation in this setting by significantly increasing bone formation, but not resorption. These data suggest a novel use of rhIGF-I to selectively stimulate bone formation in states of undernutrition and low bone turnover.

Clinically nonfunctioning pituitary tumors are monoclonal in origin.

Clinically nonfunctioning pituitary adenomas are benign neoplasms comprising approximately 25-30% of pituitary tumors. Little is known about the pathogenesis of pituitary neoplasia. Clonal analysis allows one to make the important distinction between a polyclonal proliferation in response to a stimulatory factor versus a monoclonal expansion of a genetically aberrant cell. We investigated the clonal origin of pituitary tumors using X-linked restriction fragment length polymorphisms at the phosphoglycerate kinase and hypoxanthine phosphoribosyl-transferase genes. Restriction enzymes were used to distinguish maternal and paternal X-chromosomes, and combined with a methylation-sensitive restriction enzyme to analyze allelic X-inactivation patterns in six pituitary adenomas. All six tumors showed a monoclonal pattern of X-inactivation. These data indicate that nonfunctioning pituitary adenomas are unicellular in origin, a result consistent with the hypothesis that this tumor type is due to somatic mutation.

Glycoprotein hormone genes are expressed in clinically nonfunctioning pituitary adenomas.

Approximately 25% of patients with pituitary adenomas have no clinical or biochemical evidence for excess hormone secretion and are classified as having null cell or nonfunctioning adenomas. To characterize the cell type of these tumors, we analyzed pituitary hormone gene expression in clinically nonfunctioning pituitary adenomas using specific oligonucleotide probes for the messenger (m)RNAs encoding growth hormone, prolactin, ACTH, and the glycoprotein hormone subunits, alpha, luteinizing hormone (LH)beta, follicle-stimulating hormone (FSH)beta, and thyroid-stimulating hormone (TSH)beta. Expression of one or more of the anterior pituitary hormone genes was found in 12/14 (86%) of the patients with clinically classified nonfunctioning adenomas. Expression of one or more of the glycoprotein hormone genes (alpha, LH beta, FSH beta, TSH beta) was identified most commonly (79%) with expression of multiple beta-subunit genes in many cases. Expression of alpha-subunit mRNA was found in each of the adenomas from patients expressing one of the beta-subunit mRNAs and in three patients with no detectable beta-subunit mRNA. Although FSH beta and LH beta mRNAs were found with similar frequencies in nonfunctioning adenomas, expression of FSH beta mRNA was generally much more abundant. TSH beta mRNA was detected in only one adenoma. The levels of glycoprotein hormone subunit mRNAs were variable in different adenomas, but the lengths of the mRNAs and transcriptional start sites for the alpha- and beta-subunit genes were the same in the pituitary adenomas and in normal pituitary. Growth hormone and prolactin gene expression were not observed in the nonfunctioning adenomas, but ACTH mRNA was found in a single case. Immunohistochemistry of the adenomas confirmed production of one or more pituitary hormones in 13/14 (93%) nonfunctioning tumors, with a distribution of hormone production similar to that of the hormone mRNAs. These data indicate that pituitary adenomas originating from cells producing glycoprotein hormones are common, but are difficult to recognize clinically because of the absence of characteristic endocrine syndromes and defective hormone biosynthesis and secretion.

Neural - hormonal responses to negative affective stimuli: Impact of dysphoric mood and sex.

BACKGROUND: Maladaptive responses to negative affective stimuli are pervasive, including clinically ill and healthy people, and men and women respond differently at neural and hormonal levels. Inspired by the Research Domain Criteria initiative, we used a transdiagnostic approach to investigate the impact of sex and dysphoric mood on neural-hormonal responses to negative affective stimuli. METHODS: Participants included 99 individuals with major depressive disorder, psychosis and healthy controls. Functional magnetic resonance imaging (fMRI) was complemented with real-time acquisition of hypothalamo-pituitary-adrenal (HPA) and -gonadal (HPG) hormones. fMRI data were analyzed in SPM8 and task-related connectivity was assessed using generalized psychophysiological interaction. RESULTS: Across all participants, elevated cortisol response predicted lower brain activity in orbitofrontal cortex and hypothalamus-amygdala connectivity. In those with worse dysphoric mood, elevated cortisol response predicted lower activity in hypothalamus and hippocampus. In women, elevated cortisol response was associated with lower activity in medial prefrontal cortex and low hypothalamo-hippocampal connectivity. In women with high dysphoric mood, elevated cortisol response was associated with low hypothalamo-hippocampal connectivity. There were no interactions with diagnosis or medication. LIMITATIONS: There was limited power to correct for multiple comparisons across total number of ROIs and connectivity targets; cortisol responses were relatively low. CONCLUSIONS: We conclude that the pathophysiology in neural-hormonal responses to negative affective stimuli is shared across healthy and clinical populations and varies as a function of sex and dysphoric mood. Our findings may contribute to the development of hormonal adjunctive therapeutics that are sex-dependent, underscoring the importance of one's sex to precision medicine.

Effects of testosterone replacement in androgen-deficient women with hypopituitarism: a randomized, double-blind, placebo-controlled study.

CONTEXT: Hypopituitarism in women is characterized by profound androgen deficiency due to a loss of adrenal and/or ovarian function. The effects of testosterone replacement in this population have not been reported. OBJECTIVE: The objective of the study was to determine whether physiologic testosterone replacement improves bone density, body composition, and/or neurobehavioral function in women with severe androgen deficiency secondary to hypopituitarism. DESIGN: This was a 12-month randomized, placebo-controlled study. SETTING: The study was conducted at a general clinical research center. STUDY PARTICIPANTS: Fifty-one women of reproductive age with androgen deficiency due to hypopituitarism participated. INTERVENTION: Physiologic testosterone administration using a patch that delivers 300 microg daily or placebo was administered. MAIN OUTCOME MEASURES: Bone density, fat-free mass, and fat mass were measured by dual x-ray absorptiometry. Thigh muscle and abdominal cross-sectional area were measured by computed tomography scan. Mood, sexual function, quality of life, and cognitive function were assessed using self-administered questionnaires. RESULTS: Mean free testosterone increased into the normal range during testosterone administration. Mean hip (P = 0.023) and radius (P = 0.007), but not posteroanterior spine, bone mineral density increased in the group receiving testosterone, compared with placebo, as did mean fat-free mass (P = 0.040) and thigh muscle area (P = 0.038), but there was no change in fat mass. Mood (P = 0.029) and sexual function (P = 0.044) improved, as did some aspects of quality of life, but not cognitive function. Testosterone at physiologic replacement levels was well tolerated, with few side effects. CONCLUSIONS: This is the first randomized, double-blind, placebo-controlled study to show a positive effect of testosterone on bone density, body composition, and neurobehavioral function in women with severe androgen deficiency due to hypopituitarism.

Testosterone administration in women with anorexia nervosa.

Anorexia nervosa (AN) is complicated by severe bone loss, cognitive function deficits, and a high prevalence of major depression. We hypothesized that bone formation would increase and depressive symptoms and spatial cognition would improve with short-term physiological testosterone administration. We randomized 33 women with AN and relative testosterone deficiency to transdermal testosterone (Intrinsa, Procter and Gamble Pharmaceuticals, Cincinnati, OH), 150 mug, 300 mug, or placebo, for 3 wk. At baseline, free testosterone correlated with L4 bone density (r = 0.51, P < 0.001), body mass index (r = 0.39, P = 0.02), depressive symptoms (r = -0.44, P = 0.02), and spatial cognition (r = 0.45, P = 0.04). C-terminal propeptide of type 1 collagen levels were higher during testosterone administration than placebo (P = 0.03). The change in propeptide of type 1 collagen correlated with change in free testosterone over 3 wk (r = 0.50, P = 0.02). Osteocalcin and bone-specific alkaline phosphatase did not change. Depressed patients receiving testosterone improved from severely depressed to moderately depressed; the placebo group was unchanged (P = 0.02). Spatial cognition improved in the testosterone group, compared with placebo (P = 0.0015). Therefore, short-term low-dose testosterone may improve depressive symptoms and spatial cognition in women with AN. Low-dose testosterone may also prevent decreased bone formation in AN, but because testosterone did not affect all markers of bone formation studied, further data are needed.

Truncal adiposity, relative growth hormone deficiency, and cardiovascular risk.

We hypothesized that endogenous GH would be reduced in healthy women with relative truncal adiposity despite lack of generalized obesity and that decreased GH would be associated with increased cardiovascular risk markers. Fifteen healthy female volunteers were divided into two groups, low truncal fat and high truncal fat, of comparable body mass index (BMI). Age and BMI (23.7 +/- 2.1 vs. 25.8 +/- 2.8 kg/m(2)) were similar in the two groups. Trunk fat was higher in the high-truncal-fat group, as designed. Twenty-four-hour mean GH, amplitude, and basal GH concentration were 41, 32, and 36% lower, respectively, in the high-truncal-fat group, but GH pulse frequency and IGF-I levels did not differ. In a stepwise regression model, trunk fat accounted for 38% of the variation of mean GH levels (P = 0.02), but neither total body fat nor BMI were significant determinants of mean GH in the model. There was a strong inverse association between mean 24-h GH and both truncal fat and cardiovascular risk markers, including high-sensitivity C-reactive protein. Our data suggest that visceral adiposity may be associated with reduced endogenous GH in healthy women, even in the absence of generalized obesity, and that decreased GH secretion may be associated with increased cardiovascular risk markers in this population.

Truncated activin type I receptor Alk4 isoforms are dominant negative receptors inhibiting activin signaling.

Activin, a member of the transforming growth factor beta (TGFbeta) superfamily of cytokines, inhibits cell proliferation in a variety of cell types. The functions of activin are mediated by type I and type II serine/threonine kinase receptors. The main type I receptor mediating activin signaling in human cells is ActRIB, also called Alk4. We have previously reported that several truncated Alk4 receptor isoforms are exclusively expressed in human pituitary tumors, and that the majority of such tumors did not exhibit activin-induced growth arrest in culture. We therefore studied the function of these truncated receptor isoforms. Transient expression of these truncated receptors inhibited activin-activated transcription from an activin-responsive reporter construct, 3TPLux. When each of these truncated Alk4 receptors was stably transfected into K562 cells, activin-induced expression of an endogenous gene, junB, was blocked, indicating that inhibition of gene expression also occurred at the chromosomal level. Furthermore, activin administration failed to cause growth inhibition and an increase of the G1 population in these cells. Coimmunoprecipitation experiments showed that the truncated Alk4 receptors formed complexes with type II activin receptors, but were not phosphorylated. These data indicate that the truncated activin type I receptors, predominantly expressed in human pituitary adenomas, function as dominant negative receptors to interfere with wild-type receptor function and block the antiproliferative effect of activin. This may contribute to uncontrolled pituitary cell growth and the development of human pituitary tumors.

Age and bone mass in premenopausal women.

It is important to determine the bone mass in normal premenopausal women because increasing numbers of conditions have been identified that result in premenopausal osteoporosis. The relationship between age and bone density was evaluated in 57 carefully characterized normal, premenopausal women using both single energy quantitative computed tomography (SEQCT) and dual energy (DEQCT). The mean bone density measurements were 172 mg/ml K2HPO4 SEQCT and 185 DEQCT. Bone density showed no statistically significant decline between age 18 and age 44. Single- and dual-energy data were highly correlated with each other (r = 0.89), and dual energy appeared to confer no advantage. There was an inverse relation between density and age of menarche. Bone density did not correlate with ideal body weight, percentage fat, or subcutaneous fat area.