The silent variants of pituitary tumors: demographic, radiological and molecular characteristics

INTRODUCTION

Tumors of the anterior pituitary gland (PTs) are mostly benign tumors with a low prevalence, which has nevertheless increased with advances in brain radiology techniques. Nearly half of PTs are not associated with a clinical endocrine syndrome. These tumors have been indistinctly named non-functioning pituitary adenomas (NFPAs) or silent pituitary tumors (SPTs) and the mechanisms of silencing are not fully known.

AIM

To study the frequency and characterize the silent variant of PTs in a large local series, and to assess their pituitary adenohypophyseal gene expression.

METHODS

This observational, cross-sectional study was performed in a Pituitary Tumor Center of Excellence and involved 268 PTs. After identifying the different subtypes according to the immunohistochemical (IHC) expression of adenohypophyseal hormones, we studied their gene expression by RT-qPCR.

RESULTS

We found that silent tumors were larger and more invasive, but not more proliferative than their functional counterparts. The RT-qPCR complements the IHC typification of PTs, reducing the proportion of null-cell subtype. Finally, some silent PT subtype variants showed lower specific adenohypophyseal hormone gene expression than their functional counterparts, which may contribute to the absence of endocrine manifestations.

CONCLUSIONS

This paper highlights the importance of identifying the silent variant of the PTs subtypes. As expected, silent tumors were larger and more invasive than their functioning counterparts. However, there was no difference in the proliferation activity between them. Finally, the lower specific gene expression in the silent than in the functioning counterparts of some PTs subtypes gives insights into the silencing mechanisms of PTs.

Machine-Learning Prediction of Postoperative Pituitary Hormonal Outcomes in Nonfunctioning Pituitary Adenomas: A Multicenter Study

OBJECTIVE

No accurate predictive models were identified for hormonal prognosis in non-functioning pituitary adenoma (NFPA). This study aimed to develop machine learning (ML) models to facilitate the prognostic assessment of pituitary hormonal outcomes after surgery.

METHODS

A total of 215 male patients with NFPA, who underwent surgery in four medical centers from 2015 to 2021, were retrospectively reviewed. The data were pooled after heterogeneity assessment, and they were randomly divided into training and testing sets (172:43). Six ML models and logistic regression models were developed using six anterior pituitary hormones.

RESULTS

Only thyroid-stimulating hormone (p < 0.001), follicle-stimulating hormone (p < 0.001), and prolactin (PRL; p < 0.001) decreased significantly following surgery, whereas growth hormone (GH) (p < 0.001) increased significantly. The postoperative GH (p = 0.07) levels were slightly higher in patients with gross total resection, but the PRL (p = 0.03) level was significantly lower than that in patients with subtotal resection. The optimal model achieved area-under-the-receiver-operating-characteristic-curve values of 0.82, 0.74, and 0.85 in predicting hormonal hypofunction, new deficiency, and hormonal recovery following surgery, respectively. According to feature importance analyses, the preoperative levels of the same type and other hormones were all important in predicting postoperative individual hormonal hypofunction.

CONCLUSION

Fluctuation in anterior pituitary hormones varies with increases and decreases because of transsphenoidal surgery. The ML models could accurately predict postoperative pituitary outcomes based on preoperative anterior pituitary hormones in NFPA.

Clinical and Pathological Aspects of Silent Pituitary Adenomas

CONTEXT

Silent pituitary adenomas are anterior pituitary tumors with hormone synthesis but without signs or symptoms of hormone hypersecretion. They have been increasingly recognized and represent challenging diagnostic issues.

EVIDENCE ACQUISITION

A comprehensive literature search was performed using MEDLINE and EMBASE databases from January 2000 to March 2018 with the following key words: (i) pituitary adenoma/tumor and nonfunctioning; or (ii) pituitary adenoma/tumor and silent. All titles and abstracts of the retrieved articles were reviewed, and recent advances in the field of silent pituitary adenomas were summarized.

EVIDENCE SYNTHESIS

The clinical and biochemical picture of pituitary adenomas reflects a continuum between functional and silent adenomas. Although some adenomas are truly silent, others will show some evidence of biochemical hypersecretion or could have subtle clinical signs and, therefore, can be referred to as clinically silent or "whispering" adenomas. Silent tumors seem to be more aggressive than their secreting counterparts, with a greater recurrence rate. Transcription factors for pituitary cell lineages have been introduced into the 2017 World Health Organization guidelines: steroidogenic factor 1 staining for gonadotroph lineage; PIT1 (pituitary-specific positive transcription factor 1) for growth hormone, prolactin, and TSH lineage, and TPIT for the corticotroph lineage. Prospective studies applying these criteria will establish the value of the new classification.

CONCLUSIONS

A concise review of the clinical and pathological aspects of silent pituitary adenomas was conducted in view of the new World Health Organization classification of pituitary adenomas. New classifications, novel prognostics markers, and emerging imaging and therapeutic approaches need to be evaluated to better serve this unique group of patients.

Pituitary Metastasis from Malignant Bronchial Carcinoid

Metastases from a carcinoid tumor to the pituitary gland have, to our knowledge, not been described. We present a 49-year-old woman diagnosed as having a primary carcinoid tumor arising in the submucosa of a large bronchus who 8 years later presented with multiple metastases including one to the pituitary gland, which was in partial failure of pituitary function. This case illustrates than when confronted with a pituitary tumor resembling an adenoma but negative for pituitary hormones, the possibility of a metastasis from a carcinoid tumor should be considered.

Diagnostic Accuracy of Perioperative Measurement of Basal Anterior Pituitary and Target Gland Hormones in Predicting Adrenal Insufficiency After Pituitary Surgery

The insulin tolerance test (ITT) is the gold standard for diagnosing adrenal insufficiency (AI) after pituitary surgery. The ITT is unpleasant for patients, requires close medical supervision and is contraindicated in several comorbidities. The aim of this study was to analyze whether tumor size, remission rate, preoperative, and early postoperative baseline hormone concentrations could serve as predictors of AI in order to increase the diagnostic accuracy of morning serum cortisol. This prospective study enrolled 70 consecutive patients with newly diagnosed pituitary adenomas. Thirty-seven patients had nonfunctioning pituitary adenomas (NPA), 28 had prolactinomas and 5 had somatotropinomas. Thyroxin (T4), thyrotropin (TSH), prolactin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and insulin-like growth factor 1 (IGF-I) were measured preoperatively and on the sixth postoperative day. Serum morning cortisol was measured on the third postoperative day (CORT3) as well as the sixth postoperative day (CORT6). Tumor mass was measured preoperatively and remission was assessed 3 months after surgery. An ITT was performed 3 to 6 months postoperatively. Remission was achieved in 48% of patients and AI occurred in 51%. Remission rates and tumor type were not associated with AI. CORT3 had the best predictive value for AI (area under the curve (AUC) 0.868, sensitivity 82.4%, specificity 83.3%). Tumor size, preoperative T4, postoperative T4, and TSH were also associated with AI in a multivariate regression model. A combination of all preoperative and postoperative variables (excluding serum cortisol) had a sensitivity of 75.0% and specificity of 77.8%. The predictive power of CORT3 substantially improved by adding those variables into the model (AUC 0.921, sensitivity 94.1%, specificity 78.3%, PPV 81.9%, NPV of 92.7%). In a subgroup analysis that included only female patients with NPA, LH had exactly the same predictive value as CORT3. The addition of baseline LH to CORT3, increased sensitivity to 100.0%, specificity to 88.9%, PPV to 90.4%, and NPV to 100.0%. Besides CORT3, tumor size, thyroid hormones, and gonadotropins can serve as predictors of AI. LH in postmenopausal female patients with NPA has similar diagnostic accuracy as CORT3. Further studies are needed in order to validate the scoring system proposed by this study.

Relationship between pituitary stalk (PS) visibility and the severity of hormone deficiencies: PS interruption syndrome revisited

CONTEXT

Pituitary stalk interruption syndrome (PSIS) is a rare cause of combined pituitary hormone deficiency characterized by a triad shown in pituitary imaging, yet it has never been evaluated due to the visibility of pituitary stalk (PS) in imaging findings.

OBJECTIVE

The major objective of the study was to systematically describe the disease including clinical presentations, imaging findings and to estimate the severity of anterior pituitary hormone deficiency based on the visibility of the PS.

METHODS

This was a retrospective study including 74 adult patients with PSIS in Shanghai Clinical Center for Endocrine and Metabolic Diseases between January 2010 and June 2014. Sixty had invisible PS according to the findings on MRI, while the rest had a thin or intersected PS. Basic characteristics and hormonal status were compared.

RESULTS

Of the 74 patients with PSIS, age at diagnosis was 25 (22-28) years. Absent pubertal development (97·3%) was the most common presenting symptom, followed by short stature. Insulin tolerance test (ITT) and gonadotrophin-releasing hormone (GnRH) stimulation test were used to evaluate the function of anterior pituitary. The prevalence of isolated deficiency in growth hormone (GH), gonadotrophins, corticotrophin and thyrotrophin were 100%, 97·2%, 88·2% and 70·3%, respectively. Although the ratio of each deficiency did not vary between patients with invisible PS and with visible PS, panhypopituitarism occurred significantly more frequent in patients with invisible PS. Patients with invisible PS had significantly lower levels of luteinizing hormone (LH), follicle stimulation hormone (FSH) and hormones from targeted glands including morning cortisol, 24-h urine free cortisol, free triiodothyronine (FT3), free thyroxine (FT4) and testosterone (T) in male than patients with visible PS. Moreover, patients with invisible PS had lower peak LH and FSH in GnRH stimulation test, and higher peak cortisol in ITT while peak GH remained unchanged between two groups.

CONCLUSIONS

The prevalence of multiple anterior pituitary hormone deficiency was high in adult patients with PSIS. And more importantly, we found the visibility of PS shown on MRI might be an indication of the severity of PSIS.

Evaluation of hormonal changes in menstrual cycle of women infected with pulmonary tuberculosis in Nnewi, south eastern Nigeria

BACKGROUND & OBJECTIVE

The present study was designed to evaluate the hormonal changes in menstrual cycle of premenopausal women infected with pulmonary tuberculosis in Nnamdi Azikiwe University Teaching Hospital Nnewi.

MATERIAL AND METHODS

A prospective study involving sixty-seven (67) female participants within the child-bearing age were randomly recruited and grouped based on their tuberculosis status as: Symptomatic TB infected females (n=20), Symptomatic TB infected females on ATT (n=20) and Control females (n=27). After due consent, a detailed medical history was obtained and routine investigations of pulmonary tuberculosis and confirmation using Ziehl Neelsen and sputum culture techniques for AFB and chest x-ray were done. Blood samples collected from the participants were used for hormonal assay using immunoenzymometric method.

RESULTS

The results showed that the serum levels of FSH and LH (IU/ml) were significantly higher while progesterone and estradiol were significantly lower in Symptomatic TB females compared to Symptomatic TB females on ATT at follicular and luteal phases of menstrual cycle (P<0.05). The serum levels of FSH and LH were significantly reduced in Symptomatic TB females on ATT while progesterone and estradiol were significantly increased at follicular and luteal phases of menstrual cycle (P<0.05). FSH was significantly higher at follicular phase while estradiol was significantly higher at luteal phase of menstrual cycle in Symptomatic TB females on ATT.

CONCLUSION

Tuberculosis induced hypogonadism in affected women which seemed to be reversed on treatment. Routine investigation for Tuberculosis should be done for women presenting with infertility, since early treatment can reverse the abnormality.

Sleep and hormonal changes in aging

Age-related sleep and endocrinometabolic alterations frequently interact with each other. For many hormones, sleep curtailment in young healthy subjects results in alterations strikingly similar to those observed in healthy old subjects not submitted to sleep restriction. Thus, recurrent sleep restriction, which is currently experienced by a substantial and rapidly growing proportion of children and young adults, might contribute to accelerate the senescence of endocrine and metabolic function. The mechanisms of sleep-hormonal interactions, and therefore the endocrinometabolic consequences of age-related sleep alterations, which markedly differ from one hormone to another, are reviewed in this article.

Changes in plasma melanocyte-stimulating hormone, ACTH, prolactin, GH, LH, FSH, and thyroid-stimulating hormone in response to injection of sulpiride, thyrotropin-releasing hormone, or vehicle in insulin-sensitive and -insensitive mares

Six insulin-sensitive and 6 insulin-insensitive mares were used in a replicated 3 by 3 Latin square design to determine the pituitary hormonal responses (compared with vehicle) to sulpiride and thyrotropin-releasing hormone (TRH), 2 compounds commonly used to diagnose pituitary pars intermedia dysfunction (PPID) in horses. Mares were classified as insulin sensitive or insensitive by their previous glucose responses to direct injection of human recombinant insulin. Treatment days were February 25, 2012, and March 10 and 24, 2012. Treatments were sulpiride (racemic mixture, 0.01 mg/kg BW), TRH (0.002 mg/kg BW), and vehicle (saline, 0.01 mL/kg BW) administered intravenously. Blood samples were collected via jugular catheters at -10, 0, 5, 10, 20, 30, 45, 60, 90, and 120 min relative to treatment injection. Plasma ACTH concentrations were variable and were not affected by treatment or insulin sensitivity category. Plasma melanocyte-stimulating hormone (MSH) concentrations responded (P < 0.01) to both sulpiride and TRH injection and were greater (P < 0.05) in insulin-insensitive mares than in sensitive mares. Plasma prolactin concentrations responded (P < 0.01) to both sulpiride and TRH injection, and the response was greater (P < 0.05) for sulpiride; no effect of insulin sensitivity was observed. Plasma thyroid-stimulating hormone (TSH) concentrations responded (P < 0.01) to TRH injection only and were higher (P < 0.05) in insulin-sensitive mares in almost all time periods. Plasma LH and FSH concentrations varied with time (P < 0.05), particularly in the first week of the experiment, but were not affected by treatment or insulin sensitivity category. Plasma GH concentrations were affected (P < 0.05) only by day of treatment. The greater MSH responses to sulpiride and TRH in insulin-insensitive mares were similar to, but not as exaggerated as, those observed by others for PPID horses. In addition, the reduced TSH concentrations in insulin-insensitive mares are consistent with our previous observation of elevated plasma triiodothyronine concentrations in hyperleptinemic horses (later shown to be insulin insensitive as well).

Pituitary stalk lesions: the Mayo Clinic experience

CONTEXT

Pituitary stalk lesions have various etiologies, often not clinically apparent. Pathological samples from these lesions are rarely obtained, because of the critical location and function of the hypophyseal stalk.

OBJECTIVES

The purpose of this study was to characterize the etiological spectrum of pituitary stalk lesions seen at Mayo Clinic Rochester over 20 years and to determine whether specific magnetic resonance imaging (MRI) characteristics could provide clinician guidance with regard to the etiology of infundibular lesions.

DESIGN

A retrospective review of patients with pituitary stalk lesions seen at Mayo Clinic Rochester between 1987 and 2006 was conducted. Demographic, clinical presentation, imaging, laboratory, operative, and pathology data were reviewed and are reported using descriptive statistics.

RESULTS

Of the 152 pituitary stalk lesions included, 49 (32%) were neoplastic, 30 (20%) were inflammatory, 13 (9%) were congenital anomalies, and 60 (39%) were of unclear etiology. Diabetes insipidus was diagnosed in 43 (28%) of the 152 patients, and 49 (32%) patients had at least one anterior pituitary hormone deficit. Secondary hypogonadism was the most common endocrine deficiency. Eleven of 13 congenital lesions were round in appearance and 5 of 7 patients with neurosarcoidosis confirmed by pathology had a uniformly thickened pituitary stalk on MRI. There were no statistically significant correlations between hypopituitarism and the pattern of enhancement or size of the lesion.

CONCLUSIONS

Findings on MRI remain key in guiding the diagnosis of pituitary stalk lesions, particularly when used in conjunction with other clinical clues. There are no good imaging predictors for hypopituitarism, making clinical evaluation of all patients with pituitary stalk lesions crucial.

[Metabolic syndrome and hormone profile in patients with erectile dysfunction]

OBJECTIVES

To demonstrate the existence of relation between metabolic syndrome and erectile dysfunction and to analyze the hormone profile of these patients regarding a healthy population group.

MATERIAL AND METHODS

A case-control study was designed with 65 men divided into 2 groups according to presence or non-presence of erectile dysfunction. Group A was made up of 37 men with erectile dysfunction and group B by 28 healthy men without erectile dysfunction. Ages ranged from 40 to 65 years. The presence of metabolic syndrome according to the ATPIII definition, performance of physical exercise, smoking habit, body mass index and complete hormone profile including testosterone -total, free and bioavailability, were studied.

RESULTS

Greater presence of metabolic syndrome was detected among men of Group A (72.9%) versus those of group B (17.8%) (p=0.0001). Among the parameters that make up the metabolic syndrome, there are differences between both groups in systolic and diastolic blood pressure, fast blood sugar and abdominal circumference, all these differences being significant. After performing multivariate analysis between the metabolic syndrome and erectile dysfunction adjusted for age, BMI, International Index for Erectile Function (IIEF), physical exercise and smoking habit, we have observed an independent significant relation between the metabolic syndrome and erectile dysfunction. We have not found differences between both groups in any hormone parameter.

CONCLUSION

A relationship is found between metabolic syndrome and erectile dysfunction. Thus, it seems recommendable to perform the metabolic profile and cardiovascular risk study in these patients.

Deficit in anterior pituitary function and variable immune deficiency (DAVID) in children presenting with adrenocorticotropin deficiency and severe infections

CONTEXT

Among 22 independent patients from the GENHYPOPIT network who had ACTH deficiency and no identified mutation of TPIT, three of them (13.6%) displayed common variable immunodeficiency (CVID), characterized by defective Ig production.

OBJECTIVE

Our objective was to describe an as yet unrecognized disease association.

DESIGN

We considered the hypothesis of ACTH deficiency being associated with antipituitary autoimmunity or lymphocytic hypophysitis. In the context of a functional network between the immune and endocrine systems, we also tested the hypothesis of a common genetic cause using a candidate gene approach.

SETTING

This was a multicentric study in three academic hospitals.

PATIENTS

We report four patients from three unrelated families presenting with ACTH deficiency and CVID.

MAIN OUTCOME MEASURES

Detection of antipituitary autoantibodies, and sequencing of candidate genes (LIF, IKAROS, EOS) were the main outcome measures.

RESULTS

All patients including a pedigree with two affected siblings had ACTH deficit diagnosed from 5-15 yr, with symptomatic hypoglycemia, and CVID diagnosed from 2-8 yr revealed by recurrent infections. Three of the four patients had a hypoplastic pituitary. One patient had low IGF-I and subnormal GH response to stimulation, suggesting that secretion of other pituitary hormones may also be affected. All patients proved negative for pituitary autoantibodies and had no alteration in any of the genes tested.

CONCLUSIONS

The remarkable association of two rare disorders affecting two functionally related systems in four patients from three independent pedigrees including a familial case provides strong evidence of the existence of a disease association: deficit in anterior pituitary function and variable immune deficiency, or DAVID.

The influence of cocaine-amphetamine regulated transcript (CART) on pituitary hormones, corticosterone and leptin levels in starved rats

OBJECTIVE

CART is involved in the control of food intake and hormonal secretion. We aimed to evaluate the effects of CART on hormonal profile in starved rats.

METHODS

Study group included 100 male rats. Under conditions of food limitation CART (55-102) was given centrally (icv) or peripherally (iv). Non-starved animals underwent identical procedure. Vehicle (aCSF or saline)-injected rats served and as a controls. 60 minutes after CART or vehicle administration blood was collected to assess pituitary hormones (LH, FSH, PRL, GH, ACTH, TSH), corticosterone and leptin concentrations.

RESULTS

Itracerebroventricular CART injection resulted in a significant increase in PRL, GH and corticosterone concentrations in non-starved rats compared with vehicle injected animals. However, in a group of starved animals only leptin levels were decreased in comparison with fasted controls. Peripheral CART administration caused a significant increase in PRL, GH and TSH levels in non-starved rats but no changes in investigated hormone levels were observed in starved animals when compared to saline injected controls.

CONCLUSIONS

Our results indicate that CART is able to modulate hormonal profile in a non-starved rats. However, the modulatory effect depends on the CART administration method. Interestingly, CART administration, both icv and iv, does not have an impact on pituitary hormones and corticosterone levels in a course of food limitation.

Should anterior pituitary function be tested during follow-up of all patients presenting at the emergency department because of traumatic brain injury?

CONTEXT

A wide range (15-56%) of prevalences of anterior pituitary insufficiency are reported in patients after traumatic brain injury (TBI). However, different study populations, study designs, and diagnostic procedures were used. No data are available on emergency-department-based cohorts of TBI patients.

OBJECTIVE

To assess the prevalence of pituitary dysfunction in an emergency-department-based cohort of TBI patients using strict endocrinological diagnostic criteria.

METHODS

Of all the patients presenting in the emergency department with TBI over a 2-year period, 516 matched the inclusion criteria. One hundred and seven patients (77 with mild TBI and 30 with moderate/severe TBI) agreed to participate. They were screened for anterior pituitary insufficiency by GHRH-arginine testing, evaluation of fasting morning hormone levels (cortisol, TSH, free thyroxine, FSH, LH, and 17beta-estradiol or testosterone), and menstrual history 3-30 months after TBI. Abnormal screening results were defined as low peak GH to GHRH-arginine, or low levels of any of the end-organ hormones with low or normal pituitary hormone levels. Patients with abnormal screening results were extensively evaluated, including additional hormone provocation tests (insulin tolerance test, ACTH stimulation test, and repeated GHRH-arginine test) and assessment of free testosterone levels.

RESULTS

Screening results were abnormal in 15 of 107 patients. In a subsequent extensive endocrine evaluation, anterior pituitary dysfunction was diagnosed in only one patient (partial hypocortisolism).

CONCLUSION

By applying strict diagnostic criteria to an emergency-department-based cohort of TBI patients, it was shown that anterior pituitary dysfunction is rare (<1%). Routine pituitary screening in unselected patients after TBI is unlikely to be cost-effective.

Polymorphisms of TCF7L2 and HHEX genes in Chinese women with polycystic ovary syndrome

PURPOSE

This study was to evaluate whether polymorphisms of TCF7L2 (rs7903146) and HHEX (rs1111875) genes responsible for insulin secretion are associated with the polycystic ovary syndrome (PCOS) in Chinese people.

METHODS

326 PCOS patients and 290 healthy individuals as controls were studied. Blood samples were obtained for DNA analyses and hormone measurements. Genotyping of the TCF7L2 (rs7903146) and HHEX (rs1111875) genes was carried out by the polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

We did not find statistically significant differences in the distribution of the TCF7L2 rs7903146 and HHEX rs1111875 polymorphisms between the Chinese women with PCOS and the controls. Levels of hormones such as insulin, FSH, LH, LH/FSH, P, T and E2 were also similar between the different genotypes of the genes TCF7L2 and HHEX, respectively, which was confirmed within either the PCOS subjects or controls.

CONCLUSIONS

There was no association of either of the two variants, rs7903146 of TCF7L2 and rs1111875 of HHEX, with the occurrence of PCOS in the Chinese population.

Menstrual irregularities and related plasma hormone levels in multiple sclerosis patients treated with beta interferone

Multiple sclerosis is a chronic inflammatory disease of central nervous system.Women are more susceptible to this disease. One of the obvious clinical complaints in women with multiple sclerosis specially treated with Beta Interferones is menstrual cycle irregularity. The aim of this study was to determine the prevalence of menstrual irregularities and probable changes in blood levels of related hormones (FSH, LH, PRL, TSH, T4, T3) in 58 females with definite MS treated with beta interferones versus 58 healthy women. In comparison to the control group, the patients had higher prevalence of irregular menstruation (P=0.001), oligomenorrhea (p=0.03), abnormal amount of menstrual blood flow (P=0.001), abnormal duration of menstrual flow (P=0.01) and missed period (P=0.04). Mean LH level in patients group was higher than control group (P=0.04). Hyperprolactinemia (>25.5 ng/ml) was more prevalent in patients group. There were not a significant difference in plasma levels of FSH and thyroid hormones between two groups. There were some relations between the type of Beta interferones and the subtype of menstrual irregularities in the patients. In conclusion, the results of this study emphasized the high rate of menstrual problem and changes of related plasma hormone levels in MS patients.

Central-to-peripheral fat ratio, but not peripheral body fat, is related to insulin resistance and androgen markers in polycystic ovary syndrome

BACKGROUND

Overweight, hyperandrogenism and insulin resistance are cardinal features of patients with polycystic ovary syndrome (PCOS). Women with PCOS have excess accumulation of trunkal fat and metabolic complications. Recent findings suggest that peripheral fat may have metabolic protective behaviour. The aim of this study was to investigate body fat distribution in patients with PCOS and associations of peripheral fat with metabolic and hormonal profile.

METHODS

The study included 24 patients with PCOS and a control group of 13 women. Anthropometrical evaluation and dual-energy X-ray absorptiometry to determine body composition was performed. Plasma metabolic and hormonal profiles were evaluated.

RESULTS

Patients with PCOS have increased proportion of central to peripheral fat ratio (CPFR) when compared to controls (p = 0.008). There was a positive correlation among trunkal fat, insulin, HOMA-IR and triglycerides (all p < 0.05). Regarding to peripheral fat there was no difference between groups, a trend to negative correlation to insulin appeared. Positive correlation between free androgens index and CPFR (p = 0.058) and a negative correlation between SHBG and CPFR (p = 0.016) were appeared.

CONCLUSIONS

Patients with PCOS showed an android pattern fat distribution when compared to controls. Peripheral fat contribution and its relations to androgens in this context could not be established. Android pattern of fat distribution showed inverse correlation to SHBG levels, suggesting that SHBG may be related to fat distribution.

Effect of a Somatostatin Analogue on Trophic Hormone Levels in Acromegalic Patients with Elevated hGH after Adrenomectomy and Treatment with Bromocriptine

Five female acromegalic patients who had undergone surgical adenomectomy, but still had elevated hGH serum levels, were treated with bromocriptine, 5-15 mg daily, for at least 4 months without a satisfactory response. In an attempt to lower serum hGH levels, p-NH2-Phe4-D-Trp8-somatostatin was administered, 100 micrograms as an i.v. bolus, followed by infusion of 250 micrograms over a 4 hour period. The analogue decreased hGH levels by about 50% in 3 out of 5 patients, both during bromocriptine treatment and also in its absence. Of the remaining two patients, one showed a decrease in hGH levels in response to the analogue only during bromocriptine treatment and the other only without it. Saline infusion after bromocriptine administration did not induce a decrease in hGH levels in three of these patients. Somatostatin analogue caused a fall in serum insulin levels in all but one patient, who had diabetes mellitus and in whom serum insulin was undetectable. Both hGH and insulin levels showed a significant rebound after infusion of the analogue, but returned to basal levels within 24 hours. Prolactin did not change during the analogue infusion in 4 patients with normal PRL levels. However, in one patient in whom prolactin and hGH levels were elevated during bromocriptine treatment, the infusion of somatostatin analogue decreased both hormones. The analogue induced no changes in serum TSH, FSH and LH levels of any of the patients.

Long-term insulin-dependent diabetes mellitus with secondary pituitary insufficiency and regression of retinopathy

Three women with insulin-dependent diabetes mellitus (IDDM) from childhood and early development of diabetic retinopathy are described. Insulin requirement was reduced to 5-12 IU daily in all three after relatively uncomplicated births and all had very brittle diabetes on this dosage. At re-examination 16-22 years after these births and after 34-42 years of IDDM, regression of retinopathy was observed in two patients, while the third had a light retinopathy at the same level as initially. Other diabetic complications were few and none of the patients had nephropathy. Pituitary examination revealed incomplete hypopituitarism in all cases, human growth hormone (HGH) being the sole common factor lacking. These findings and a review of four similar cases reported previously lend some support to the hypothesis of HGH as a possible pathogenetic co-determinant in the development of diabetic retinopathy.

beta-adrenoceptor blockade and physical activity: cardiovascular and metabolic aspects

This paper assesses mechanisms that may contribute to the higher incidence of increased muscle fatigue during exercise and reduced exercise performance as observed with selective compared with non-selective beta-adrenoceptor antagonists. Published data and the results obtained in 8 healthy subjects (mean age 23 years) studied before and after acute beta-adrenoceptor blockade with pindolol (nonselective, 10 mg) and metoprolol (beta 1-receptor selective, 100 mg) suggest that the differences in the cardiovascular and respiratory effects between the 2 types of antagonists are marginal and cannot explain the discrepancies concerning exercise perception and performance. Conversely, basic differences between the 2 types of antagonists were shown in different groups of hypertensive men (mean age 32 years) studied before and after 4 weeks of treatment with pindolol (15 mg), and with metoprolol (200 mg) and acebutolol (cardioselective, 500 mg), by single crossover technique. Whereas lipolysis was similarly inhibited by both selective and non-selective antagonists, hypoglycaemia occurred only under non-selective blockade. It apparently reflects the inhibition of glycogen breakdown; concomitant rises in plasma adrenaline and ACTH probably reflect counter-regulatory mechanisms.

Predictors of anterior pituitary insufficiency after traumatic brain injury

BACKGROUND

Several studies have reported a high prevalence of hypopituitarism after traumatic brain injury (TBI). Risk stratification is a prerequisite for cost-effective hormonal screening of these patients. However, it is still unclear which risk factors predispose patients to develop anterior hypopituitarism after TBI.

OBJECTIVE

To assess clinical and radiological risk factors for post-traumatic hypopituitarism.

PATIENTS AND METHODS

Seventy-eight consecutive patients (52 men, 26 women; mean age 36.0 years, range 18-65 years) with mild, moderate or severe TBI were studied. Endocrine and clinical parameters were assessed 3 and 12 months after TBI.

RESULTS

We found diffuse axonal injury, basal skull fracture and older age to be major risk factors of post-traumatic hypopituitarism.

CONCLUSIONS

We have defined specific risk factors for the development of post-traumatic hypopituitarism that are consistent with pathophysiological considerations. These findings might help to identify at-risk patients.

Pituitary functions in the acute phase of traumatic brain injury: are they related to severity of the injury or mortality?

PRIMARY OBJECTIVE

There are only limited data regarding pituitary functions in the acute phase of traumatic brain injury (TBI) and previous studies have been conducted in only small cohorts of subjects. Therefore we have investigated the pituitary functions in the early acute phase, within 24 hours of trauma, in 104 patients with TBI. Additionally, the relationships between basal pituitary hormones, severity of the trauma and mortality due to trauma were also investigated.

METHODS AND PROCEDURES

One hundred and four TBI patients were included in the study consecutively. All patients underwent basal hormonal evaluation within the first 24 hours of admission. Twenty of 104 patients died during the acute phase.

MAIN OUTCOMES

Prolactin levels were negatively correlated with the Glasgow coma scale (GCS), cortisol levels were positively correlated with the GCS and cortisol levels were positively correlated with ACTH levels. Additionally there was a significant positive correlation between the total testosterone levels and the GCS in males. Logistic regression analysis revealed that mortality after TBI was unrelated to basal pituitary hormone levels. However age and GCS were significantly related to the mortality. The percentages of pituitary hormone deficiencies were as follows: 3.8% had TSH deficiency, 40.0% had gonadotrophin deficiency, 8.8% had ACTH deficiency and 20.0% had GH deficiency.

CONCLUSIONS

Present data clearly demonstrate that pituitary function is disturbed in TBI and the most frequently deficient pituitary hormones were gonadotrophins in the early acute phase of TBI. Basal hormone levels including cortisol, prolactin and total testosterone were related to the severity of the trauma. However there was no relation between basal hormones and mortality due to TBI. Age and GCS were significantly related to mortality.

Small pituitary size in children with Fanconi anemia

BACKGROUND

Fanconi anemia (FA) is a genetic disorder associated with multiple congenital anomalies, bone marrow failure, and pituitary hypofunction including hypogonadism, thyroid dysfunction, and growth hormone (GH) deficiency.

PROCEDURE

Among 44 patients with FA referred to Cincinnati Children's Hospital Medical Center (CCHMC) between 1975 and 2005, 33 had neuroimaging studies, including 11 cranial magnetic resonance imaging (MRIs). Two separate measurements per patient from these MRIs were used to evaluate pituitary height compared to on-site control data of similar measurements of cranial MRIs on 22 age and gender-matched children without any pathology involving the hypothalamic-pituitary system. Growth pattern and endocrine studies were reviewed to assess potential correlation with pituitary size.

RESULTS

When compared to the age-gender matched on-site control sample, the mean pituitary height of FA patients was significantly smaller (P < 0.0001; mean +/- SE from mixed effects model with age and gender as covariates: 3.96 +/- 0.32 vs. 5.76 +/- 0.24). Upon further adjusting for the effect of the small head size by including bi-parietal diameter (BPD) as a covariate, the difference remained statistically significant (P = 0.0013). Findings on the growth pattern and endocrinological measurements are as follows: 50% of patients with small pituitary gland were short. GH and adrenal function tests were normal in all tested patients. Thyroid, pubertal status, and glucose regulation were abnormal in 30, 50, and 75% of patients tested.

CONCLUSIONS

Children with FA tend to have unsuspected small pituitary glands beyond what is expected from the effects of their stunted growth. Further studies are required to reveal the clinical implications of this finding.

Reproductive profile of physically active men after exhaustive endurance exercise

The purpose of this study on non-professional (recreational) athletes was two-fold: 1) to determine if endurance exercise (EE) routinely used by professional athletes would produce reproductive changes in the general population, and 2) to assess reversion. Short-term exhaustive endurance exercise (EEE) can produce alterations in the hypothalamic-pituitary-gonadal (HPG) axis with subsequent fertility changes. Sixteen healthy adult male volunteers were divided into experimental (8) and control (8) groups for the exercise period. A cycloergometer provided EEE for a period of 2 weeks. The experimental group exercised four times a week; controls were without EEE. The hormonal and seminological profiles of all subjects were evaluated. Two weeks of EEE produced hormonal and seminological values in the experimental group that were statistically different from their own pre-treatment values (FSH: 3.33 +/- 1.7; LH: 3.73 +/- 1.36; sperm concentration/ml: 42.50 +/- 29.46; type a velocity: 25.23 +/- 10.9; type d velocity: 46.18 +/- 15.81; % of normal forms: 10.42 +/- 1.97) as well as from the pre- and post-treatment control group values. The measured parameters almost returned to pre-treatment levels in the experimental group 2 - 3 days after EEE ended. From this study we concluded that when subjected to EEE, individuals drawn from a recreational exercising life style experienced changes similar to those observed in studies done with athletes, and short-term EEE induced a reversible alteration to the HPG axis.

Idiopathic Premature Ovarian Failure in 63 Young Women

BACKGROUND

Premature ovarian failure (POF) in adolescents is defined as primary or secondary amenorrhea associated with high follicle-stimulating hormone (FSH) levels. In normal 46,XX patients, its etiology is most often unknown. We have evaluated the clinical, hormonal and ovarian phenotypes in patients with a normal karyotype who were diagnosed with POF before the age of 18.

METHODS

Sixty-three patients were included in this retrospective study.

RESULTS

The mean patient age was 20.4 years. The patients presented with three clinical patterns: lack of pubertal development (n = 23), primary amenorrhea with interrupted puberty (n = 18), and secondary amenorrhea with normal puberty (n = 22). Ten patients had a familial history of POF and 6 presented with hypothyroidism. The FSH, estradiol and inhibin B levels were not statistically different in the three clinical groups. Fifty percent of the patients presented small ovaries (length <2 cm) at ultrasonography. The presence of follicles was found at histology in only 7 of the 27 patients who underwent an ovarian biopsy.

CONCLUSION

46,XX patients presenting with early POF rarely presented a specific, identifiable disorder. We discuss the clinical management and different diagnosis strategies to improve our current knowledge of this syndrome.

Effects of megestrol acetate on pituitary function and end-organ hormone secretion: A post hoc analysis of serum samples from a 12-week study in healthy older men

BACKGROUND

Megestrol acetate (MA) is a synthetic progestin commonly used to promote weight gain in malnourished older individuals. In small studies, MA administration has been associated with reduced serum cortisol concentrations in patients with cancer or AIDS. The impact of MA on the pituitary secretion of adrenocorticotropic hormone (ACTH) and other hormones is unclear, and the prevalence and extent of hypocortisolemia in older individuals after MA treatment is unknown. A randomized, placebo-controlled study of the effects of testosterone (T) and resistance training (RT) on body composition after MA administration in older men has been reported previously.

OBJECTIVE

The purpose of this post hoc analysis was to examine the effect of 12 weeks of MA on pituitary function and end-organ hormone secretion in healthy older individuals using frozen serum samples from that study.

METHODS

The previous study was conducted at the Department of Geriatrics, Donald W. Reynolds Center on Aging and the General Clinical Research Center at The University of Arkansas for Medical Sciences, Little Rock, Arkansas. Healthy male volunteers aged 60 to 85 years were recruited from the center and were randomly assigned to 1 of 4 study groups: RT + T, T, RT + placebo (P), or P. Subjects enrolled in the RT groups underwent supervised upper- and lower-body strength-training exercises 3 d/wk at 80% of 1 repetition maximum. Subjects in the groups to receive T received injections of testosterone enanthate 100 mg i.m. QW for 12 weeks. Subjects receiving P were given 1-mL saline injections i.m. QW for 12 weeks. All subjects received MA 800 mg p.o. QD concurrently for 12 weeks. For the present analysis, serum concentrations of the pituitary hormones follicle-stimulating hormone (FSH), thyroid-stimulating hormone (TSH), ACTH, prolactin (PRL), and luteinizing hormone (LH), as well as the end-organ hormones estradiol (E2), cortisol, free T4, and T, were measured in samples obtained at baseline (week 0) and after 12 weeks of MA treatment.

RESULTS

Serum samples from 21 men (mean [SD]age, 67.0 [7.3]years; mean [SD] body mass index, 23.1 [10.4] kg/m2; mean [SD] percentage of body fat, 22.5% [8.8%]; RT + T, T, RT + P, and P groups, n = 4, 5, 6, and 6 subjects, respectively) were available from the original study. The mean percentage changes from baseline in serum pituitary hormone concentrations after 12 weeks of MA administration were as follows: TSH, -14.7%; ACTH, -89.5%; PRL, 162.2%; and LH, -49.0%; (P = 0.03, <0.001, <0.001, and <0.001, respectively). The mean (SD) percentage changes from baseline in serum end-organ hormone concentrations with MA at 12 weeks were as follows: E2, 181.6%; and cortisol, -90.8% (both, P < 0.001). In the P and RT + P groups, the mean percentage changes from baseline in T were -84% and -85%, respectively (both, P < 0.001). FSH and free T4 concentrations were not significantly changed.

CONCLUSIONS

This analysis of serum samples from healthy older men suggests that MA administration significantly affected the secretion of several pituitary hormones and end-organ hormone synthesis. Most notably, ACTH secretion and serum cortisol levels were statistically significantly suppressed in 20 of 21 subjects, without the development of clinically significant adrenal suppression.

24-hour pituitary and adrenal hormone profiles in chronic fatigue syndrome

OBJECTIVES

Disturbances of neuroendocrine function, particularly the hypothalamo-pituitary-adrenal (HPA) axis, have been implicated in the pathophysiology of chronic fatigue syndrome (CFS). However, few studies have attempted to measure blood levels of pituitary or adrenal hormones across a whole 24-hour period in CFS, and those that did so have used infrequent sampling periods. Our aim was to assess 24-hour pituitary and adrenal function using frequent blood sampling.

METHODS

We recruited 15 medication-free patients with CFS without comorbid psychiatric disorder and 10 healthy control subjects. Blood samples were collected over 24 hours and assayed for cortisol, corticotropin (ACTH), growth hormone (GH), and prolactin (PRL) levels on an hourly basis during daytime hours (10 am to 10 pm) and every 15 minutes thereafter (10 pm to 10 am).

RESULTS

Repeated-measures analyses of variance were undertaken using hormone levels averaged over 2-hour blocks to smooth curves by reducing the influence of sample timing relative to secretory burst. For ACTH, there was both a main effect of group, suggesting reduced mean ACTH secretion in patients with CFS over the whole monitoring period, and a group-by-time interaction, suggesting a differential pattern of ACTH release. Post hoc analysis showed reduced ACTH levels in CFS during the 8 am to 10 am period. In contrast, there were no significant abnormalities in the levels of cortisol, GH, and PRL in patients with CFS over the full cycle compared with control subjects. Cosinor analysis found no differences in the cortisol circadian rhythm parameters, but the ACTH rhythm did differ, patients with CFS showing an earlier acrophase.

CONCLUSIONS

Patients with CFS demonstrated subtle alterations in HPA axis activity characterized by reduced ACTH over a full circadian cycle and reduced levels during the usual morning physiological peak ACTH secretion. This provides further evidence of subtle dysregulation of the HPA axis in CFS. Whether this dysregulation is a primary feature of the illness or instead represents a biologic effect secondary to having the illness itself remains unclear.

Presurgical octreotide treatment in acromegaly: no improvement of final growth hormone (GH) concentration and pituitary function. A long-term case-control study

BACKGROUND

The effect of presurgical long-acting somatostatin analogue (SSA) treatment on operative outcome in acromegaly is as yet uncertain and long-term observations are lacking. We evaluated in an acromegaly case-control study the effect of octreotide pre-treatment on short- and long-term postoperative GH concentrations, pituitary function and glucose tolerance.

METHODS

48 patients with a pituitary macro-adenoma - micro- and giant adenomas excluded - were evaluated. 24 patients received presurgical octreotide treatment (secondary surgery, prospectively studied). Another 24 thoroughly matched patients had been operated on without prior octreotide therapy (primary surgery, retrospective evaluation). No patient had received any other treatment prior to operation/octreotide. Standardized testing was performed at diagnosis, following octreotide treatment, after surgery and then yearly for 10.3+/-0.9 yrs (mean+/-SE, primary surgery) and 4.1+/-0.6 yrs (secondary surgery). Immediate and 4-year postoperative results were compared. All work-up was strictly identical in both groups, except for imaging techniques. "Partial remission" was defined as mean GH profile (6-h/7-point) concentration <2.5 microg/L, and "complete remission" as GH nadir <1 microg/L during OGTT plus normal IGF-I concentration (when available).

FINDINGS

The median profile GH (microg/L) values and the OGTT GH nadir values post-surgery (2.4/1.0 vs 1.8/0.7, primary and secondary surgery, resp.) as well as 4 yrs later (2.1/1.15 vs 2.3/0.8) were not significantly different between the groups. The 10-year results of the primary surgery group were not significantly different from its 4-year results. Subgroup analysis of pre-treated patients revealed no significant difference between those with and without tumour shrinkage, or between those with and without parasellar tumour extension. Postoperatively pituitary function was not significantly different between the groups. After 4-years the pituitary-adrenal axis was slightly more impaired in the secondary surgery group rather than following primary surgery, while the pituitary-gonadal axis was not different.

CONCLUSION

Presurgical octreotide treatment has no significant short- or long-term beneficial effect on GH concentration or pituitary function.

Pituitary gland and pregnancy

The hypothalamic-pituitary-adrenal axis is central to mammalian reproductive function, including conception, pregnancy maintenance, parturition, and breastfeeding. Pregnancy is associated with substantial physiologic changes within this endocrine axis to meet the demands of pregnancy, which include support of the fetus (volume support, nutritional and oxygen supply, clearance of fetal waste), protection of the fetus (from starvation, drugs, toxins), preparation of the uterus for labor, and protection of the mother from potential cardiovascular injury at delivery. This article reviews the anatomy, embryology, and physiology of the pituitary. The effect of pregnancy on pituitary structure and function, in health and disease, also is discussed.

Effect of interferon-gamma treatment on 24-hour variations in plasma ACTH, growth hormone, prolactin, luteinizing hormone and follicle-stimulating hormone of male rats

OBJECTIVE

Interferon-gamma (IFN-gamma) is a cytokine produced by T helper cells on antigenic challenge that may affect the release of several pituitary hormones. However, in vitro or in vivo studies have yielded disparate results with stimulatory, inhibitory or absent effects of IFN on pituitary hormone release. One of the reasons for these discrepancies could be that hormone changes were commonly assessed at a single time point in the day-night cycle. In this study we measured the circadian pattern of plasma ACTH, growth hormone (GH), prolactin, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) at 6 different time points within a 24-hour cycle in adult male Wistar rats.

METHODS

Groups of 6-8 rats kept under light from 08:00 to 20:00 h daily received 5 daily injections intraperitoneally of human IFN-gamma (10(5) IU/kg body weight) or saline at 08:30 h. Plasma ACTH, GH, prolactin, LH and FSH levels were measured by a homologous specific double antibody RIA.

RESULTS

A factorial ANOVA for main effects indicated a significant 43% increase of circulating prolactin in IFN-gamma-treated rats. Time of day changes were significant for the five hormones examined and these diurnal variations became altered by IFN-gamma administration, with a phase advance of ACTH peak, a suppression of the rest phase peak of GH, the appearance of a second peak of prolactin at an early phase of daily photoperiod, and the blunting of the 24-hour variations of plasma FSH.

CONCLUSION

The data point out an effect of IFN-gamma on the mechanisms responsible for the circadian organization of pituitary hormone release.

[Pituitary insufficiency following head injury--how common is it, and what is to be done?]

In Germany,traumatic brain injury (TBI) has an annual incidence of approximately 200000. In contrast to earlier assumptions, pituitary insufficiency is a common complication of TBI, with a prevalence of 30-50%. Since the symptoms are often nonspecific and may be masked by the sequelae of head injury, it may go unrecognized and may possibly aggravate the symptomatology of such injury. It is therefore to be recommended that patients who suffer a head injury should be examined to exclude pituitary gland insufficiency, by measuring the basal hormone level--where necessary in combination with stimulation tests.

Effect of ethanol on 24-hour hormonal changes in peripubertal male rats

We analyzed the effect of chronic (4 weeks) ethanol feeding on 24-h variation of pituitary-testicular function in peripubertal male Wistar rats by measuring circulating concentrations of prolactin, follicle-stimulating hormone, luteinizing hormone, testosterone, and thyrotropin. Animals were maintained under a 12-h light: 12-h dark photoperiod and received a liquid diet for 4 weeks, starting on day 35 of life. The ethanol-fed group received a diet similar to that provided to control animals, except that maltose was replaced isocalorically with ethanol. Ethanol replacement provided 36% of the total caloric content of the diet. Rats were killed at one of six times around the clock, beginning at zeitgeber time (ZT) 1 (ZT 0 = lights on). In ethanol-fed rats globally, secretion of prolactin was augmented, whereas secretion of follicle-stimulating hormone, luteinizing hormone, testosterone, and thyrotropin was decreased. Significant changes in the 24-h secretory pattern of circulating hormones occurred in rats receiving ethanol, including the appearance of two peaks (at ZT 1 and ZT 9), rather than one peak, of follicle-stimulating hormone during the inactive phase of the daily cycle, suppression of the maximum plasma luteinizing hormone concentration during the first part of the inactive phase, and appearance of a second peak of testosterone and prolactin during the second part of the inactive phase (at ZT 5 and ZT 9, respectively) and of a second peak of plasma thyrotropin during the first part of the active phase (at ZT 13). The significant positive correlation between testosterone and individual luteinizing hormone and prolactin concentrations in control animals was no longer observed after ethanol administration. Chronic ethanol administration presumably affects the endogenous clock that modulates the circadian variation of the pituitary-gonadal axis and thyrotropin release in growing male rats.

Endocrinological outcome of different treatment options in children with craniopharyngioma: a retrospective analysis of 66 cases

Craniopharyngioma is one of the leading causes of hypothalamic-pituitary dysfunction in childhood, caused either by the tumor itself or the consequences of treatment. Tumor management in terms of recurrence rate, quality of life and complications is still controversial. Sixty-six patients with craniopharyngioma at pediatric age were reviewed for symptoms, signs, types of treatment, recurrence rates, complications, and endocrinological outcome. The majority of symptoms was related to the neurological system. Complaints only affecting the endocrinological system were seen in 6% of patients. The most frequent complaints were headache and vomiting (74.2%). The main endocrinological complaints were polyuria and polydipsia (15%), and lassitude (10.6%). Although short stature was a symptom in 9.1% of patients, it was a finding in 39.7% of patients. Plain skull X-rays raised the suspicion of intracranial tumor in more than 90% of children with craniopharyngioma. Recurrence rates were independent of the extent of tumor removal (total or subtotal). The frequency of endocrine dysfunction increased significantly after treatment. The most frequent hypothalamic-pituitary dysfunction was growth hormone deficiency (100%) and gonadotropin deficiency (80%). Hypothyroidism was diagnosed in 74% of patients. The frequency of hypothalamic-pituitary dysfunction was not affected by the extent of tumor removal. Radiotherapy did not increase the frequency of endocrine dysfunctions further. In conclusion, growth follow-up in childhood seems to be an important indicator of craniopharyngioma in early diagnosis. Radiotherapy and extent of tumor removal - either total or subtotal - did not influence endocrine outcome.

Immunoexpression of androgen receptors and aromatase in testes of patient with Klinefelter's syndrome

Klinefelter's syndrome (47, XXY) is the most common chromosome aneuploidy in men and is usually characterized by underdeveloped testes and sterility. The aim of the present study was to detect cellular distribution of androgen receptors (AR) and aromatase in testes of patient with KS. The tissue sections were processed for morphological and immunohistochemical staining. Additionally, levels of FSH, LH, PRL, estradiol, and testosterone were measured in the plasma. Morphological analysis revealed a complete absence of spermatogenesis. No germ cells were present in seminiferous tubules. In some tubules, nests of apparently degenerating Sertoli cells were found. In the interstitium, Leydig cell hyperplasia was observed. Using immunohistochemistry, nuclear AR staining was detected in Sertoli cells and peritubular cells, whereas in Leydig cells the staining was exclusively cytoplasmic. The immunostaining of aromatase was detected in the cytoplasm of Sertoli cells and Leydig cells. Increased levels of gonadotropins and decreased level of testosterone concomitantly with the cytoplasmic localization of AR in Leydig cells might contribute to the impaired testicular function in patient with KS.

Sleep enhances the human antibody response to hepatitis A vaccination

OBJECTIVE

The common belief that sleep supports immune defense has received surprisingly little direct experimental support. The antibody response to vaccination provides a valid tool to assess the influence of sleep on adaptive immune functioning in humans, which is also clinically relevant.

METHODS

Two groups of healthy humans (N = 19) not previously infected with hepatitis A virus (HAV) were studied. On the night after primary vaccination with inactivated HAV, which took place at 0900 hours, one group had regular sleep. The other group stayed awake, and did not sleep before 2100 hours the following day. HAV antibody titers were measured repeatedly until 28 days after vaccination. Plasma hormone concentrations and white blood cell (WBC) subset counts were determined on the night and day after vaccination.

RESULTS

Subjects who had regular sleep after vaccination, displayed a nearly two-fold higher HAV antibody titer after 4 weeks than subjects staying awake on this night (p=.018). Compared with wakefulness, sleep after vaccination distinctly increased release of several immune-stimulating hormones including growth hormone, prolactin, and dopamine (p <.01). Concentrations of thyrotropin, norepinephrine, and epinephrine were lowered by sleep (p <.02), whereas sleep only marginally influenced WBC subset counts.

CONCLUSIONS

Data suggest that sleep compared with sleep deprivation on the night after vaccination improves the formation of antigen-specific immune defense as reflected by antibody production in humans. Sleep presumably acts by inducing a hormonal environment in secondary lymphoid tissues, enhancing lymphocyte proliferation and differentiation and finally antibody synthesis. Results underscore the importance of sleep for immunocompetence.

Association of Turner's syndrome and hypopituitarism: a patient report

Turner's syndrome (TS) is associated with a wide spectrum of clinical features, such as short stature and gonadal dysgenesis. While it is a common chromosomal abnormality, the association of Turner's syndrome and hypopituitarism is an uncommon finding. We describe here a girl with concomitant pituitary insufficiency and gonadal dysgenesis. When she was 7 years old, her mother reported that she suffered from frontal headache, asthenia and delayed growth. Basal laboratory thyroid evaluation suggested hypothyroidism, with no evidence of autoimmune disease association. She began taking L-thyroxine. At age 11 years, short stature and complaints of frontal headache still persisted. She was still prepubertal and her bone age was delayed by 2.2 years. Her karyotype was compatible with 45,X/46,XX (100 cells analyzed by FISH) and a CT scan showed empty sella. At 12 years of age, an anterior pituitary stimulation test with insulin, gonadotropin-releasing hormone (GnRH) and thyrotropin-releasing hormone (TRH) showed gonadotropin, thyrotropin (TSH) and growth hormone (GH) deficiency. Replacement therapy with GH was begun and she grew 12 cm during the first year of treatment. This report illustrates that, despite the high incidence of sinusitis, short stature and primary hypothyroidism in TS, we should consider the presence of hypopituitarism when the patient presents low levels of TSH with negative thyroid antibodies and inappropriately low levels of gonadotropins for patients with gonadal dysgenesis.

On the role of menopause for sleep-endocrine alterations associated with major depression

Aging and menopause are associated with alterations of the sleep EEG, while age-related changes of the hypothalamo-pituitary-adrenal (HPA) axis remain controversial. Major depression is also associated with typical sleep-endocrine changes, including enhanced activity of the HPA axis, while an influence of age and gender on these alterations is less clear. To test the hypothesis that after menopause sleep-endocrine alterations associated with major depression are accentuated, we examined the sleep EEG and nocturnal hormone secretion (ACTH, cortisol, GH, estradiol, LH, FSH, and leptin) in 16 drug-free female patients, mostly with the first episode of a major depressive disorder (seven pre- and nine postmenopausal subjects) and 19 female controls (10 subjects in the early follicular phase and nine postmenopausal subjects). Nocturnal cortisol secretion was increased in postmenopausal patients with depression, while a decrease was noted in postmenopausal controls. Sleep alterations typically associated with depression, namely a reduction in sleep continuity and slow wave sleep (SWS) and an increase in REM density, were prominent in post- but not in premenopausal patients. An inverse correlation was noted between the decline in SWS and sleep continuity and FSH secretion in patients with depression, suggesting a role of menopause for these sleep-endocrine alterations typically associated with major depression. In contrast, in premenopausal patients we noted primarily a shift in SWS and delta-EEG activity from the first to the second non-REM period, which was not related to age or hormone secretion. Though the relatively small number of subjects per group precludes a definitive conclusion, our data open up the possibility that the sleep-endocrine changes typically associated with major depression are most prominent in postmenopausal patients. Whether the predominant alteration of the distribution of SWS and delta EEG activity in younger patients with a first episode of major depression has a predictive value for the future course of the disease remains to be investigated.

Growth hormone treatment in a girl with Prader Willi syndrome

Prader Willi syndrome (PWS) is a rare endocrine-metabolic disorder that is characterised by neonatal hypotonia, hyperphagia, marked obesity, short stature, hypogonadism and behavioural problems. 7-20% percent of these children develop diabetes mellitus. A large number of individuals with PWS show growth hormone (GH) deficiency. Recent studies indicate beneficial effects of GH replacement therapy not only for their linear growth but also for correction of metabolic dysfunction. In the present communication this article details about the therapeutic outcome in a girl with PWS who received recombinant growth hormone (rGH), Genotropin. Some carry-over therapeutic benefits have been observed even after discontinuation of rGH.

[Hormonal interactions of parathormone and calcium metabolism]

The possible hormonal interactions of parathormone and extracellular calcium level with other endocrine systems were studied. Primary hyperparathyroidism was used first as a clinical model, in which hypercalcemia and normocalcemia occurs before and after surgery, respectively. An increased activity of renin-aldosterone system related to parathormone was found in hyperparathyroidism, and surgery resulted in a small decrease in blood pressure. This change was accompanied by a significant decrease in the activity of the renin-aldosterone system indicating the cessation of the secondary hyperaldosteronism. The role of a relative hyperinsulinism, occurring in hyperparathyroidism, in the pathogenesis of hypertension was not proved. The basal and stimulated secretion of thyreotrophin, the basal growth hormone level, and the stimulated prolactin secretion increased after surgery. Follicle stimulating hormone and luteinizing hormone secretions remained unchanged. The results suggest that extracellular calcium may reversibly modify the secretion of certain anterior pituitary hormones and their stimulus-induced responses. In the second disease, growth hormone deficiency syndrome, studied, long-term growth hormone replacement therapy results in significant but transient changes in bone metabolism: calcium-, alkaline phosphatase-, and phosphate levels increase until 6 to 18 months as compared to the initial values; then these parameters decrease to the baseline level. Parathormone decreases until the first year then returns to the baseline level. Osteocalcin shows similar temporary changes. In spite of the above transient changes, osteodensity increases after 12 months of treatment, and further improvement can be seen after 18 and 24 months, i.e. GH treatment exerts a biphasic effect on bones; resorption increases first followed by an increase in formation. Based on the above results, it can be concluded that both parathormone and extracellular calcium are able to influence the secretion of certain hormones; and--as it is shown in growth hormone replacement therapy--other hormones may cause certain effect on them, too. The better understanding of these interactions may result in a better understanding of the pathomechanism of certain diseases and the improvement of their treatment.

Chronic renal failure and anterior hypophysial hormones

Kidneys are not only organs with an excretory function but they produce their own endocrine factors which are involved in supporting homeostasis in the organism. The kidneys are the organs in which metabolism and biodegradation of many hormones take place. Together with the liver, the kidneys actively take part in the catabolism of hormones.

A low dose of ghrelin stimulates growth hormone (GH) release synergistically with GH-releasing hormone in humans

The synergistic relationship between GH-releasing secretagogue (GHS) and GH-releasing hormone (GHRH) with respect to GH secretion is well known. In the present study, we report a similar relationship between GHRH and ghrelin, a recently identified endogenous ligand for the GHS receptor. In normal male adults, various doses of ghrelin were intravenously administered alone or together with 1.0 microg/kg GHRH. At small doses of 0.08 and 0.2 microg/kg ghrelin, combined administration of the two peptides significantly stimulated GH release in a synergistic manner; the mean GH response values of the two peptide combinations were more than the summed mean GH response values of each peptide alone (P < 0.05). In addition, at 1.0 microg/kg ghrelin, the tendency of the synergistic effect was observed, although the comparison was not statistically significant probably due to a submaximal dose ceiling effect. No synergistic effects with respect to ACTH or prolactin secretion were observed. In conclusion, the synergistic interaction between ghrelin and GHRH was clearly shown and might be useful for a provocation test to diagnose GH deficiency.

Reproductive effects of nonylphenol in rats after gavage administration: a two-generation study

The potential reproductive toxicity of nonylphenol (NP) was assessed in a two-generation reproductive toxicity study. Groups of 25 male and female Crj:CD (SD) IGS rats were given NP by gavage at levels of 2, 10, or 50 mg/kg, and 25 males and females were given corn oil as controls. No adverse changes in clinical signs were observed in any rats throughout the study. Significant increases in the liver, kidney and pituitary gland weights in males, and decreases in thymus weight in males and in ovary weight in females were observed in the 50 mg/kg group. NP did not affect sperm characteristics or the estrous cycle at any dose administered. A significant increase in the TSH level was observed in males in the 50 mg/kg group. No adverse effects of NP on reproduction were found. At necropsy, no treatment-related alterations were observed in any organs including the reproductive tissues in any group. Histopathologic changes were found in the liver of male and female rats and kidneys of males in the 50 mg/kg group. The viability of offspring from postnatal day 0 to 4 in the 50 mg/kg group was reduced as compared with that in the controls, although growth was not affected by NP administration. On postnatal day 22, an increase in the serum FSH level and decrease in T(3) level for males, and decreases in LH and TSH levels and an increase in T(3) levels for females were observed in the 50 mg/kg group. NP did not affect the timing of preputial separation, while vaginal opening was accelerated in the 50 mg/kg group. No adverse changes were found in behavior or learning in the offspring of NP-treated groups. There were no treatment-related changes in any reproductive parameter, including estrous cycle, mating, fertility, delivery, and lactation, except for significant decreases in the numbers of implantation sites and live pups, and a significant decrease in ovary weight in the 50 mg/kg group. Kidney and liver weight were increased in males in the 50 mg/kg group. Histopathologic examination revealed changes in the liver of males and females of the 50 mg/kg group. No treatment-related changes were observed in the sperm characteristics. Hormone data should be interpreted cautiously until the findings are repeated and confirmed by further studies. These results of NP suggested that the no observed adverse effect level (NOAEL) on reproductive capacity is 50 mg/kg/day or greater in parent animals, and 10 mg/kg/day in the next generation under the present experimental condition.

Long-term transgene expression within the anterior pituitary gland in situ: impact on circulating hormone levels, cellular and antibody-mediated immune responses

Adenoviral vectors have been identified as useful tools for gene transfer to the pituitary gland with the aim of providing therapeutic treatments for pituitary diseases. Although successful adenovirus-mediated gene transfer to the pituitary has been shown, the duration of transgene expression, local immune responses and consequences on circulating pituitary hormone levels have not been investigated. These are critical not only for the successful implementation of these gene transfer techniques both for physiological and/or therapeutic applications but also for assessing the safety of these approaches. We have therefore assessed duration and levels of transgene expression 3 days, 14 days, 1, 2, and 3 months after delivery of adenoviruses expressing herpes simplex virus type 1 thymidine kinase (HSV1-TK), under the control of the major immediate early human cytomegalovirus (RAd-hCMV/TK) or human PRL (RAd-hPrl/TK) promoters, to the anterior pituitary (AP) gland in situ. The presence of vector genome and cellular immune infiltrates within the AP gland were also studied along with the levels of circulating anti-adenovirus neutralizing antibodies and AP hormones in sera. Ubiquitous or cell-type specific expression of HSV1-TK within the AP gland was seen from RAd-hCMV/TK and RAd-hPrl/TK respectively at all time points, although a reduction in expression was seen over time. PCR amplification of HSV1-TK specific sequences showed the persistence of adenoviral genomes for up to 3 months. Analysis of the AP showed the presence of a virus-induced inflammation that peaked around day 14 and was resolved between 2-3 months. ED1-positive macrophages, CD8-positive T-cells and CD161-positive NK cells were identified up to 1 month after virus administration. A virus-induced humoral immune response was also present as anti-adenovirus neutralizing antibodies were detected from 14 days after virus administration. Levels of circulating pituitary hormones were unaffected by virus administration with the exception of the stress hormone ACTH which was increased at 3 days but normalized by 14 days. In conclusion, our data indicates that adenovirus-mediated delivery to the AP gland in situ may be a useful tool for the treatment of pituitary diseases as no major cytotoxicity or disruption of AP hormonal functions are seen. Despite of this, further developments to this approach still need to be made to combat the reduced transgene expression seen over time and the induction of virus-induced immune responses.

Chronic sustained stress increases levels of anterior pituitary prolactin mRNA

Our laboratory is investigating the effects of chronic stress on physiological, endocrine and behavioral measures, in order to elucidate the neuronal substrates for the pathophysiological consequences of stress in humans. In these studies, we have employed a rodent model of sustained stress in which rats are exposed to around-the-clock intermittent footshock that can be avoided or escaped by rats in the controllable stress group, but not by rats in the uncontrollable stress group. Each rat in the uncontrollable stress group is paired (yoked) to a rat in the controllable stress group such that the controllable stress group rat avoids or escapes shock for both rats. A third group of rats receives no shock (controls). We have previously reported that in male rats, plasma prolactin levels were elevated after 3 days of stress in both stress groups. In the present experiments we determined whether the increases in plasma prolactin were correlated with increases in anterior pituitary prolactin mRNA. In addition, we measured hormones and mRNA at three time points and we examined these responses in female as well as male rats. Adult male and female Sprague-Dawley rats were exposed to chronic stress for 1, 3 or 14 days. In unstressed control rats, levels of anterior pituitary prolactin mRNA were fivefold higher in female as compared to male rats. However, stress increased levels of anterior pituitary prolactin mRNA over baseline in both genders. After 1 day of stress, anterior pituitary prolactin mRNA levels increased in male and female rats belonging to both stress groups, with no significant difference seen between the uncontrollable vs. controllable stress groups. After 3 days of stress, anterior pituitary prolactin mRNA levels were even more elevated, and rats in the uncontrollable stress group had higher anterior pituitary prolactin mRNA levels than those in the controllable stress group. After 14 days of stress, there were no significant differences in control and stressed groups with respect to anterior pituitary prolactin mRNA. These data suggest that chronic sustained stress increases the synthesis of anterior pituitary prolactin mRNA during the first days of stress, and that levels return to prestress values sometime between 3 and 14 days of stress.

Combined pituitary hormone deficiency in german shepherd dogs with dwarfism

In German shepherd dogs pituitary dwarfism is known as an autosomal recessive inherited abnormality. To investigate whether the function of cells other than the somatotropes may also be impaired in this disease, the secretory capacity of the pituitary anterior lobe (AL) cells was studied by a combined pituitary AL stimulation test with four releasing hormones (4RH test) in four male and four female German shepherd dwarfs. In addition, the morphology of the pituitary was investigated by computed tomography. The physical features of the eight German shepherd dwarfs were primarily characterized by growth retardation and stagnant development of the hair coat. The results of the 4RH test confirmed the presence of hyposomatotropism. The basal plasma TSH and prolactin concentrations were also low and did not change upon stimulation. Basal plasma concentrations of LH were relatively low and responded only slightly to suprapituitary stimulation. With respect to the plasma FSH levels there was a clear gender difference. In the males plasma FSH concentrations remained below the detection limit throughout the 4RH test, whereas in the females the basal plasma FSH levels were slightly lower and there was only a small increase following suprapituitary stimulation, compared with the values in age-matched controls. In contrast, basal and stimulated plasma ACTH concentrations did not differ between the dwarfs and the controls. Computed tomography of the pituitary fossa revealed a normal sized pituitary with cysts in five dogs, an enlarged pituitary with cysts in two dogs, and a small pituitary gland without cysts in the remaining dog. The results of this study demonstrate that German shepherd dwarfs have a combined deficiency of GH, TSH, and prolactin together with impaired release of gonadotropins, whereas ACTH secretion is preserved. The combined pituitary hormone deficiency is associated with cyst formation and pituitary hypoplasia.

Transcriptional targeting to anterior pituitary lactotrophic cells using recombinant adenovirus vectors in vitro and in vivo in normal and estrogen/sulpiride-induced hyperplastic anterior pituitaries

The use of pituitary cell type-specific promoters is a powerful molecular tool to achieve pituitary cell type-specific transcriptional targeting of transgenes encoded by viral vectors. It has recently been proposed that transcriptional targeting of therapeutic genes could be harnessed as a gene therapy strategy for the treatment of pituitary disease. We describe the successful use of the human PRL promoter (hPrl) encoded within recombinant adenovirus vectors to target transgene expression of Herpes Simplex Virus Type 1-Thymidine Kinase (HSV1-TK) or beta-galactosidase to lactotrophic cells in vitro and in vivo. Functionally, the restriction of expression of HSV1-TK to lactotrophic tumor cells, using the hPrl promoter, resulted in the cell type-specific induction of apoptosis in the lactotrophic GH3 tumor cell line, in the presence of ganciclovir (GCV). In the corticotrophic AtT20 cell line, we detected neither HSV1-TK expression, nor apoptosis in the presence of GCV. The hPrl promoter encoded within a recombinant adenoviral vector also restricted transgene expression to lactotrophic cells in primary anterior pituitary (AP) cultures, and importantly, within the anterior pituitary gland in vivo. When the HSV1-TK driven by hPrl promoter was used in an in vivo model ofestrogen/sulpiride lactotroph induced hyperplasia within the AP in situ, the treatment was not effective in either reducing the weight of the gland, the number of lactotrophic cells within the transduced area in vivo, or the circulating PRL levels. This is in contrast to the human cytomegalovirus promoter (hCMV) driving expression of HSV1-TK in the same experimental paradigm, which was effective in reducing pituitary weight and circulating PRL levels. Our results have important implications in the design of gene therapy strategies for pituitary tumors. We demonstrate that both the choice of the in vivo animal model, i.e. adenoma in the AP gland in situ, and the particular gene therapy strategy chosen, i.e. use of strong ubiquitous promoters vs. weaker but cell type-specific promoters, determine the experimental therapeutic outcome.