"Management of andrological disorders from childhood and adolescence to transition age: guidelines from the Italian Society of Andrology and Sexual Medicine (SIAMS) in collaboration with the Italian Society for Pediatric Endocrinology and Diabetology (SIEDP)-Part-1".

PURPOSE: Andrological pathologies in the adulthood are often the results of conditions that originate during childhood and adolescence and sometimes even during gestation and neonatal period. Unfortunately, the reports in the literature concerning pediatric andrological diseases are scares and mainly concerning single issues. Furthermore, no shared position statement are so far available. METHODS: The Italian Society of Andrology and Sexual Medicine (SIAMS) commissioned an expert task force involving the Italian Society of Pediatric Endocrinology and Diabetology (SIEDP) to provide an updated guideline on the diagnosis and management of andrological disorders from childhood and adolescence to transition age. Derived recommendations were based on the grading of recommendations, assessment, development, and evaluation (GRADE) system. RESULTS: A literature search of articles in English for the term "varicoceles", "gynecomastia", "fertility preservation", "macroorchidism", "precocious puberty" and "pubertal delay" has been performed. Three major aspects for each considered disorder were assessed including diagnosis, clinical management, and treatment. Recommendations and suggestions have been provided for each of the mentioned andrological disorders. CONCLUSIONS: These are the first guidelines based on a multidisciplinary approach that involves important societies related to the field of andrological medicine from pediatric to transition and adult ages. This fruitful discussion allowed for a general agreement on several recommendations and suggestions to be reached, which can support all stakeholders in improving andrological and general health of the transitional age.

Gender-affirming hormone treatment: friend or foe? Long-term follow-up of 755 transgender people.

PURPOSE: Gender-affirming hormone treatment (GAHT) is one of the main demands of transgender and gender diverse (TGD) people, who are usually categorised as transgender assigned-male-at birth (AMAB) and assigned-female-at birth (AFAB). The aim of the study is to investigate the long-term therapeutic management of GAHT, considering hormonal targets, treatment adjustments and GAHT safety. METHODS: A retrospective, longitudinal, observational, multicentre clinical study was carried out. Transgender people, both AMAB and AFAB, were recruited from two Endocrinology Units in Italy (Turin and Modena) between 2005 and 2022. Each subject was managed with specific and personalized follow-up depending on the clinical practice of the Centre. All clinical data routinely collected were extracted, including anthropometric and biochemical parameters, lifestyle habits, GAHT regime, and cardiovascular events. RESULTS: Three-hundred and two transgender AFAB and 453 transgender AMAB were included. Similar follow-up duration (p = 0.974) and visits' number (p = 0.384) were detected between groups. The transgender AFAB group reached therapeutic goals in less time (p = 0.002), fewer visits (p = 0.006) and fewer adjustments of GAHT scheme (p = 0.024). Accordingly, transgender AFAB showed a higher adherence to medical prescriptions compared to transgender AMAB people (p < 0.001). No significantly increased rate of cardiovascular events was detected in both groups. CONCLUSION: Our real-world clinical study shows that transgender AFAB achieve hormone target earlier and more frequently in comparison to transgender AMAB individuals. Therefore, transgender AMAB people may require more frequent check-ups in order to tailor feminizing GAHT and increase therapeutic adherence.

Adult- and late-onset male hypogonadism: the clinical practice guidelines of the Italian Society of Andrology and Sexual Medicine (SIAMS) and the Italian Society of Endocrinology (SIE).

PURPOSE: To provide the evidence-based recommendations on the role of testosterone (T) on age-related symptoms and signs remains. METHODS: The Italian Society of Andrology and Sexual Medicine (SIAMS) and the and the Italian Society of Endocrinology (SIE) commissioned an expert task force to provide an updated guideline on adult-onset male hypogonadism. Derived recommendations were based on Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. RESULTS: Clinical diagnosis of adult-onset hypogonadism should be based on a combination of clinical and biochemical parameters. Testosterone replacement therapy (TRT) should be offered to all symptomatic subjects with hypogonadism after the exclusion of possible contraindications. T gels and the long-acting injectable T are currently available preparations showing the best efficacy/safety profile. TRT can improve all aspects of sexual function, although its effect is limited in more complicated patients. Body composition (reducing fat mass and increasing lean mass) is improved after TRT, either in subjects with or without metabolic syndrome or type 2 diabetes. Conversely, the role of TRT in improving glycometabolic control is more conflicting. TRT can result in increasing bone mineral density, particularly at lumbar site, but no information on fracture risk is available. Limited data support the use of TRT for improving other outcomes, including mood frailty and mobility. CONCLUSIONS: TRT can improve sexual function and body composition particularly in less complicated adult and in aging subjects with hypogonadism. When hypogonadism is adequately diagnosed, T appropriately prescribed and subjects correctly followed up, no short-term increased risk of adverse events is observed. Longer and larger studies are advisable to better clarify TRT long-term efficacy/safety profile.

First baseline data of the Klinefelter ItaliaN Group (KING) cohort: clinical features of adult with Klinefelter syndrome in Italy.

BACKGROUND: Klinefelter syndrome (KS) is frustratingly under-diagnosed. KS have a broad spectrum of clinical features, making it difficult to identify.  OBJECTIVE: We describe KS clinical presentation in a large Italian cohort. DESIGN: This is the first observational cohort study within a national network, the Klinefelter ItaliaN Group (KING). Primary outcomes were to describe the basic clinical features and the actual phenotype of KS in Italy. Secondary outcomes were to determine age at diagnosis and geographical distribution. METHODS: We performed a basic phenotyping and evaluation of the hormonal values of 609 adult KS patients. RESULTS: Mean age at diagnosis was 37.4 ± 13.4 years. The overall mean testicular size was 3 ml, and 2.5 ml in both testes in untreated KS group. BMI was 26.6 ± 5.8 kg/m2, and 25.5% of KS had metabolic syndrome (MetS). LH and FSH were increased, and mean total testosterone were 350 ± 9.1 ng/dl. A descriptive analysis showed that 329 KS patients were evaluated in Northern Italy, 76 in Central and 204 in Southern Italy. Analysis of variance demonstrated significant statistical differences (p < 0001) between the age at diagnosis of the three geographical groups. Compared with the expected number among male patients matched for age in Italy, only 16% of KS patients received a diagnosis. CONCLUSIONS: These data are the results of the only national database available that collects the clinical and hormonal data of the KS patients, currently referred at the KING centers. In Italy the typical KS patient is overweight, with small testes, and elevated LH and FSH. Only 25.5% of them are diagnosed with MetS. Early detection and timely treatment are mandatory.

Thyroid function in Klinefelter syndrome: a multicentre study from KING group.

PURPOSE: The prevalence and the etiopathogenesis of thyroid dysfunctions in Klinefelter syndrome (KS) are still unclear. The primary aim of this study was to evaluate the pathogenetic role of hypogonadism in the thyroid disorders described in KS, with the scope to distinguish between patients with KS and hypogonadism due to other causes (Kallmann syndrome, idiopathic hypogonadotropic hypogonadism, iatrogenic hypogonadism and acquired hypogonadotropic hypogonadism after surgical removal of pituitary adenomas) called non-KS. Therefore, we evaluated thyroid function in KS and in non-KS hypogonadal patients. METHODS: This is a case-control multicentre study from KING group: Endocrinology clinics in university-affiliated medical centres. One hundred and seventy four KS, and sixty-two non-KS hypogonadal men were enrolled. The primary outcome was the prevalence of thyroid diseases in KS and in non-KS. Changes in hormonal parameters were evaluated. Exclusion criterion was secondary hypothyroidism. Analyses were performed using Student's t test. Mann-Whitney test and Chi-square test. RESULTS: FT4 was significantly lower in KS vs non-KS. KS and non-KS presented similar TSH and testosterone levels. Hashimoto's thyroiditis (HT) was diagnosed in 7% of KS. Five KS developed hypothyroidism. The ratio FT3/FT4 was similar in both groups. TSH index was 1.9 in KS and 2.3 in non-KS. Adjustment for differences in age, sample size and concomitant disease in multivariate models did not alter the results. CONCLUSIONS: We demonstrated in KS no etiopathogenic link to hypogonadism or change in the set point of thyrotrophic control in the altered FT4 production. The prevalence of HT in KS was similar to normal male population, showing absence of increased risk of HT associated with the XXY karyotype.

Impaired taste sensation in type 2 diabetic patients without chronic complications: a case-control study.

PURPOSE: Few and contradictory data suggest changes in taste perception in type 2 diabetes (T2DM), potentially altering food choices. We, therefore, analyzed taste recognition thresholds in T2DM patients with good metabolic control and free of conditions potentially impacting on taste, compared with age-, body mass index-, and sex-matched normoglycemic controls. METHODS: An ascending-concentration method was used, employing sucrose (sweet), sodium chloride (salty), citric acid (sour), and quinine hydrochloride (bitter), diluted in increasing concentration solutions. The recognition threshold was the lowest concentration of correct taste identification. RESULTS: The recognition thresholds for the four tastes were higher in T2DM patients. In a multiple regression model, T2DM [ß = 0.95; 95% CI 0.32-1.58; p = 0.004 (salty); ß = 0.61; 0.19-1.03; p = 0.006 (sweet); ß = 0.78; 0.15-1.40; p = 0.016 (sour); ß = 0.74; 0.22-1.25; p = 0.006 (bitter)] and waist circumference [ß = 0.05; 0.01-0.08; p = 0.012 (salty); ß = 0.03; 0.01-0.05; p = 0.020 (sweet); ß = 0.04; 0.01-0.08; p = 0.020 (sour); ß = 0.04; 0.01-0.07; p = 0.007 (bitter)] were associated with the recognition thresholds. Age was associated with salty (ß = 0.06; 0.01-0.12; p = 0.027) and BMI with sweet thresholds (ß = 0.06; 0.01-0.11; p = 0.019). CONCLUSIONS: Taste recognition thresholds were higher in uncomplicated T2DM, and central obesity was significantly associated with this impairment. Hypogeusia may be an early sign of diabetic neuropathy and be implicated in the poor compliance of these patients to dietary recommendations.

Treating varicocele in 2018: current knowledge and treatment options.

PURPOSE: Varicocele is defined as a state of varicosity and tortuosity of the pampiniform plexus around the testis caused by retrograde blood flow through the internal spermatic vein. The prevalence of clinically relevant varicocele ranges from 5 to 20% in the male population and is often associated with infertility and reduction of sperm quality. In this review, the pathophysiology and clinical aspects of varicocele are reviewed along with therapeutic options and treatment effects on sperm parameters and fertility both in adult and in pediatric/adolescent subjects. METHODS: We conducted a Medline and a PubMed search from 1965 to 2018 to identify publications related to varicocele clinical aspects, treatment procedures and treatment outcomes. Keywords used for the search were: "varicocele", "varicocelectomy", "sclerotherapy", "male infertility", "subfertility", and "semen abnormalities". RESULTS: Data from a large number of studies in adolescent and adult males indicate that varicocele correction improves semen parameters in the majority of patients, reducing oxidative stress and improving sperm nuclear DNA integrity either with surgical or percutaneous approach. CONCLUSIONS: Varicocele repair seems to represent a cost-effective therapeutic option for all males (both adolescent and adults) with a clinical varicocele in the presence of testicular hypotrophy, worsening sperm alterations or infertility. On the other hand, some investigators questioned the role of varicocelectomy in the era of assisted reproduction. Thus, a better understanding of the pathophysiology of varicocele-associated male subfertility is of paramount importance to elucidating the deleterious effects of varicocele on spermatogenesis and possibly formulating new treatment strategies.

Steroid myopathy: some unresolved issues.

Steroid myopathy is a non-inflammatory toxic myopathy that occurs as side effect of exogenous and endogenous glucocorticoid excess. The purpose of this review is to examine issues that limit our understanding of this myopathy with respect to nosology, etiopathogenesis, conditioning factors, and muscle fiber selectivity. We suggest that if more data were available on these issues, the understanding of steroid myopathy would be enhanced substantially, thus allowing an early detection of its occurrence (before the appearance of clinical or laboratory signs) and a proper treatment of the patients.

Correlation between genotype and hormonal levels in heterozygous mutation carriers and non-carriers of 21-hydroxylase deficiency.

Congenital adrenal hyperplasia, both in its classic (CCAH) and non-classic form (NCAH), is a morbid condition sustained by the absent or reduced function of one of the enzymes involved in cortisol biosynthesis - mainly 21 hydroxylase - associated with different levels of clinical androgenization. In a wide group of relatives of patients affected by CCAH and NCAH (no.=222) and healthy volunteers (no.=30), a clinical, hormonal and genetic evaluation was performed in order to differentiate between the condition of heterozygous mutation carrier and non-carrier of any among 21-hydroxylase gene (CYP21) mutations. This study shows that clinical presentation and basal 17α-hydroxyprogesterone (17α-OHP) are not able to differentiate between heterozygous carriers and non-carriers, whereas 17α-OHP value after ACTH bolus is significantly different between heterozygous carriers and non-carriers: p<0.001 with a cut-off value of 3 ng/ml (90% sensitivity and 74,3% specificity). Moreover, our data indicate that 17α-OHP response to ACTH may be a useful tool to select subjects for genetic analysis.

Growth hormone/insulin-like growth factor-I axis in obstructive sleep apnea syndrome: an update.

Obstructive sleep apnea syndrome (OSAS) is a serious, prevalent condition that has significant mortality and morbidity when untreated. It is strongly associated with obesity and is characterized by changes in the serum levels or secretory patterns of several hormones. In particular, obese patients with OSAS show a peculiar reduction of both spontaneous and stimulated GH secretion coupled with reduced IGF-I concentrations and impaired peripheral sensitivity to GH. These endocrine abnormalities are more marked than those observed in non-apneic obese subjects, and are likely to be due to the effects of hypoxia and sleep fragmentation on hormone secretory pattern. The GH/IGF-I axis activity disruption can be responsible, at least in part, for metabolic alterations, which are common in OSAS and increase the risk of cardiovascular events as well as mortality. Effective assessment and management of OSAS may correct endocrine changes, improve quality of life, and prevent associated morbidity or death.

Myoelectric fatigue profiles of three knee extensor muscles.

Aims of the present study were to: 1) investigate the differences between the myoelectric fatigue profiles of the vasti muscles of the quadriceps during electrically evoked contractions; 2) compare the myoelectric fatigue profiles of the vasti muscles between sedentary subjects and rowers; 3) analyze motor unit activation order during stimulation of the vasti muscles. In nine sedentary subjects and nine rowers surface EMG signals were detected during electrically elicited contractions of the following three muscles: vastus medialis obliquus (VMO), vastus lateralis (VL), and vastus medialis longus (VML). M-waves were recorded as the muscles were stimulated with both variable (increasing-decreasing) and constant stimulation intensities. Changes in M-wave conduction velocity (CV) during trains with non-constant current were adopted for the study of the motor unit recruitment order. Rates of change of myoelectric signal variables were adopted to assess myoelectric manifestations of fatigue during stimulation trains with constant current. We found that: 1) VL muscle was more fatigable than vastus medialis muscles; 2) VL and VML muscles of rowers resulted less fatigable than sedentary subjects; and 3) in the three muscles, motor units tended to be recruited in order of increasing CV and derecruited in order of decreasing CV with increasing/decreasing stimulation current.

Risk behaviours and alcohol in adolescence are negatively associated with testicular volume: results from the Amico-Andrologo survey.

BACKGROUND: Risk factors established during adolescence affect health outcomes in adulthood, although little is known about how adolescent health risk behaviours (HRBs) affect testicular development and reproductive health. OBJECTIVES: To assess prevalence of HRBs among last year high school students; to describe the most prevalent andrological disorders in this cohort; to explore HRBs associated with andrological disorders and investigate factors possibly associated with impaired testicular development in puberty. MATERIALS AND METHODS: The Amico-Andrologo Survey is a permanent nationwide surveillance programme conducted by the Italian Society of Andrology and Sexual Medicine and supported by the Ministry of Health. A nationally representative survey of final-year male high school students was conducted using a validated structured interview (n = 10124) and medical examination (n = 3816). RESULTS: Smoking (32.6%), drinking (80.6%) and use of illegal drugs (46.5%) are common in adolescence. 16.6% of subjects were overweight, 3.1% were underweight and 2.3% were obese. Among sexually active students (60.3%), unprotected sex was very common (48.3%). Only 11.6% had been treated for andrological disorders, despite an abnormal clinical examination in 34.6%. Bilateral testicular hypotrophy (14.0%), varicocoele (27.1%) and phimosis (7.1%) were the most prevalent disorders; 5.1% complained of premature ejaculation and 4.7% had an STI. Underweight and heavy alcohol or drug use were associated with testicular hypotrophy. HRBs emerged as significant predictors of testicular hypotrophy, explaining up to 9.6% of its variance. Limitations include risk of selection bias for voluntary physical examination and recall bias for the self-compiled questionnaire. DISCUSSION: There is an emerging global adverse trend of HRBs in male high school students. A significant proportion of adolescent males with unsuspected andrological disorders engage in behaviours that could impair testicular development. CONCLUSION: Greater attention to the prevention of andrological health in adolescence is needed.

Changes in awakening cortisol response and midnight salivary cortisol are sensitive markers of strenuous training-induced fatigue.

The aim of the study was to examine the effects of strenuous training on the hypothalamic- pituitary-adrenal axis activity. Exercise tests and saliva collections for analysis of awakening cortisol response (ACR) and midnight cortisol were performed before and after a 7-day period of intensified training in a group of 15 soccer players. Intensified training resulted in a performance decrement as shown by the pre-post-training changes in maximal values of counter movement jump (CMJ) height (p=0.008). Cortisol assessment during the first 30 min after awakening showed significant increases both before and after the 7-day period and post-training ACR higher than pre-training ACR (p<0.001). Midnight cortisol also significantly increased after training (mean+/-SD, before: 3.0+/-0.7 nmol/l vs after: 5.9+/-3.3 nmol/l; p=0.017). The analysis of individual data showed an important inter-individual variability in the pre-post-training changes: several subjects increased post-awakening peak of cortisol, rate of cortisol increase from awakening to peak, and area under the curve (AUC) values, whereas other subjects showed no training-related increases. Significant correlations were observed between pre-post-training change in CMJ and in the following variables: awakening cortisol (r=0.74), post-awakening peak of cortisol (r=0.81), rate of cortisol increase (r=0.75), and AUC (r=0.79). Briefly, the lower the performance decrease, the higher the training-associated ACR increase. These data could indicate that a dysregulated adaptation to exercise occurred in athletes who experienced a higher performance decrease after training and lower (or absent) hormonal changes. Future studies are needed to elucidate the physiological determinants which underlie the exercise-elicited changes in ACR and in midnight cortisol levels and their value in predicting impaired adaptations to exercise.

Corticotroph axis sensitivity after exercise: comparison between elite athletes and sedentary subjects.

Strenuous exercise activates the hypothalamic-pituitary-adrenal (HPA) axis. Several reports showed that physical training is associated with a decreased efficiency of the feedback control of HPA axis. The aims of the present study were: 1) to evaluate the differences in the mechanical, hormonal, and lactate responses to a high-intensity isokinetic exercise among different groups of competitive athletes (CA, no.=20) of power and endurance disciplines and sedentary controls (SED, no.=10); 2) to determine the effects of the training status on the HPA axis responsiveness following exercise, as indirectly evaluated by the rates of ACTH, cortisol, and DHEA recovery after exercise. CA and SED fulfilled eight sets of twenty concentric contractions of the knee extensors at 180 degrees/sec angular velocity throughout a constant range of motion (100 degrees). There was a rest period of 30 sec between each set and a 3-min rest period between the two legs. Before, immediately after the isokinetic exercise and at different times in the subsequent 120 min of recovery, blood and saliva were sampled to determine plasma ACTH, salivary cortisol, serum DHEA, and serum lactate concentrations. CA showed a higher cortisol response to exercise than SED, whereas no differences were found in the responses of ACTH, DHEA and lactate. In the athlete group the exercise-induced increases of ACTH, cortisol, and lactate were higher in power athletes with respect to endurance athletes. No differences were observed between athletes and SED in the rates of hormonal recovery after exercise: this finding does not support the concept that a reduced feedback control of HPA axis can represent a feature of trained individuals.

Effects of recombinant human insulin-like growth factor I administration on the growth hormone (gh) response to GH-releasing hormone in obesity.

Circulating GH levels are reduced in obesity due to true reduction of the 24-h GH production rate. GH insufficiency in obesity might reflect neuroendocrine abnormalities and/or alterations in peripheral hormones and metabolic factors. The somatotroph response to provocative stimuli including GHRH is markedly blunted in obese patients. However, the somatotroph responsiveness to GHRH in obesity shows also peculiar refractoriness to the inhibitory effect of glucose load. In this present study we aimed at verifying the effect of low dose rhIGF-I (20 microgram/kg, sc, at 0 min) on the GH response to GHRH (1 microgram/kg, iv, at 180 min) in obesity. With this goal in mind, six obese women with abdominal adiposity [OB; age (mean +/- SEM), 32.3 +/- 4.4 yr; body mass index, 32.8 +/- 2.3 kg/m(2)] were studied. The effects of recombinant human insulin-like growth factor I (rhIGF-I) administration on circulating total IGF-I, insulin, and glucose levels were also evaluated. The results in OB were compared with those recorded in age-matched lean women (NW; age, 28.3 +/- 1.2 yr; body mass index, 20.1 +/- 0.5 kg/m(2)), in whom the inhibitory effect of rhIGF-I had already been shown. Basal IGF-I levels in OB were similar to those in NW (199.7 +/- 33.3 vs. 274.4 +/- 25.3 microgram/L). The mean GH concentration over 3 h (from 0-180 min) in OB was lower than that in NW (0.9 +/- 0.4 vs. 2.6 +/- 0.8 microgram/L; P = NS). Administration of GHRH induced a GH response in OB lower than that in NW (area under the curve from 180-270 min, 576.5 +/- 137.5 vs. 1315.9 +/- 189.9 microgram/L.min; P < 0.02). Administration of rhIGF-I increased circulating IGF-I levels in both groups to the same percent extent (326.8 +/- 28.3 and 420.3 +/- 26.5 microgram/L in OB and NW, respectively). rhIGF-I administration inhibited the GH response to GHRH in OB (240.1 +/- 99.6 microgram/L; P < 0.05) as well as in NW (730.2 +/- 288.1 microgram/L; P < 0.05), although it failed to lower the mean GH concentration over 3 h in either OB or NW. After rhIGF-I the GH response to GHRH in OB was slight and was still lower (P < 0.05) than that in NW; in fact, the percent decreases were similar in both groups (44.21 +/- 14.06 and 48.21 +/- 13.95 microgram/L, in OB and NW, respectively). The mean insulin (107.1 +/- 21.9 and 36.8 +/- 7.2 pmol/L), but not glucose (4.0 +/- 0.3 and 4.1 +/- 0.1 mmol/L), levels calculated over 270 min, were higher (P = 0.005) in OB than in NW; rhIGF-I administration did not modify insulin and glucose levels in either group. Our study shows that the sc administration of a low rhIGF-I dose inhibits the somatotroph responsiveness to GHRH in obese as well as in normal subjects, indicating that somatotroph sensitivity to the inhibitory effect of rhIGF-I is preserved in obesity.

Effects of recombinant human insulin-like growth factor I administration on spontaneous and growth hormone (GH)-releasing hormone-stimulated GH secretion in anorexia nervosa.

Exaggerated GH and reduced insulin-like growth factor I (IGF-I) levels are common features in anorexia nervosa (AN). A reduction of the negative IGF-I feedback could account, in part, for GH hypersecretion. To ascertain this, we studied the effects of recombinant human (rh)IGF-I on spontaneous and GH-releasing hormone (GHRH)-stimulated GH secretion in nine women with AN [body mass index, 14.1 +/- 0.6 kg/m2] and in weight matched controls (normal weight). Mean basal GH concentrations (mGHc) and GHRH (2.0 microg/kg, iv) stimulation were significantly higher in AN. rhIGF-I administration (20 microg/kg, sc) significantly reduced mGHc in AN (P < 0.01), but not normal weight, and inhibited peak GH response to GHRH in both groups; mGHc and peak GH, however, persisted at a significantly higher level in AN. Insulin, glucose, and IGFBP-1 basal levels were similar in both groups. rhIGF-I inhibited insulin in AN, whereas glucose remained unaffected in both groups. IGFBP-1 increased in both groups (P < 0.05), with significantly higher levels in AN. IGFBP-3 was under basal conditions at a lower level in AN (P < 0.05) and remained unaffected by rhIGF-I. This study demonstrates that a low rhIGF-I dose inhibits, but does not normalize, spontaneous and GHRH-stimulated GH secretion in AN, pointing also to the existence of a defective hypothalamic control of GH release. Moreover, the increased IGFBP-1 levels might curtail the negative IGF-I feedback in AN.

Stimulatory effect of adrenocorticotropin on cortisol, aldosterone, and dehydroepiandrosterone secretion in normal humans: dose-response study.

The short ACTH test is widely used in clinical practice for the diagnosis of adrenal insufficiency. It is classically performed administering 250.0 microg ACTH(1-24) although 1.0 microg ACTH dose has been reported having maximal stimulatory effect on cortisol levels in normal subjects. We aimed to define the maximal and the minimal stimulatory ACTH dose on cortisol, aldosterone, and dehydroepiandrosterone (DHEA) in humans. To this goal, in 12 normal volunteers (6 males and 6 females; age, 22-34 yr; body mass index 20-25 kg/m2; body surface 1.6-1.9 m2), we studied the dose-response effect of eight ACTH doses (0.01, 0.03, 0.06, 0.125, 0.5, 1.0, 25.0, and 250.0 microg) on cortisol, aldosterone, and DHEA levels. Each ACTH dose administered at 0 min was followed by a second ACTH dose of 250.0 microg at +60 min. The cortisol delta areas under response curve (deltaAUCs) after all ACTH doses, apart from 0.01 microg, were significantly higher (P < 0.02) than that after placebo, showing a clear dose-response relationship (P < 0.001). The doses of 0.03 and 1.0 microg ACTH were the minimal and maximal effective doses, respectively. The cortisol response to 250.0 microg ACTH was not modified by pretreatment with 0.01, 0.03, and 0.06 microg ACTH doses, whereas it was progressively reduced by increasing the dose of ACTH pretreatment (P < 0.001). The aldosterone deltaAUCs to all but 0.01 microg ACTH doses were significantly higher (P < 0.02) than that after placebo, showing a clear dose-response relationship (P < 0.001). The dose of 0.03 microg was the minimal effective stimulating dose, whereas 25.0 microg showed the same aldosterone-releasing effect of 250.0 microg. The aldosterone response to 250.0 microg ACTH, preceeded by placebo, was not modified by pretreatment with 0.01 and 0.03 microg ACTH doses, whereas it was reduced by increasing the dose of ACTH pretreatment (P < 0.05-0.02). The DHEA deltaAUCs to all ACTH doses were significantly higher (P < 0.01) than that after placebo, showing a clear dose-response relationship (P < 0.001). The doses of 0.01 and 1.0 microg ACTH were the minimal and maximal effective dose, respectively. The DHEA response to 250.0 microg ACTH was not modified by pretreatment with 0.01, 0.03, 0.06, and 0.125 microg ACTH doses, whereas it was progressively reduced by pretreatment with 0.5, 1.0, and 25.0 microg ACTH doses (P < 0.01). In conclusion, these results show that an extremely low ACTH dose is needed to stimulate adrenal steroids and, among them, DHEA seems the most sensitive to corticotropin stimulation.

Arginine counteracts the inhibitory effect of recombinant human insulin-like growth factor I on the somatotroph responsiveness to growth hormone-releasing hormone in humans.

Insulin-like growth factor I (IGF-I) exerts a negative feedback effect on GH secretion via either direct actions at the pituitary level or indirect ones at the hypothalamic level, through stimulation of somatostatin (SS) and/or inhibition of GHRH release. In fact, recombinant human IGF-I (rhIGF-I) in humans inhibits spontaneous GH secretion as well as the GH response to GHRH and even more to GH/GH-releasing peptides, whose main action is on the hypothalamus, antagonizing SS and enhancing GHRH activity. The aim of the present study was to further clarify in humans the mechanisms underlying IGF-I-induced inhibition of somatotroph secretion. In six normal young volunteers (all women; mean +/- SEM: age, 28.3+/-1.2 yr; body mass index, 21.3+/-1.2 kg/m2) we studied the GH response to GHRH (1 microg/kg, iv, at 0 min), both alone and combined with arginine (ARG; 0.5 g/kg, iv, from 0-30 min), which probably acts via inhibition of hypothalamic SS release, after pretreatment with rhIGF-I (20 microg/kg, sc, at -180 min) or placebo. rhIGF-I increased circulating IGF-I levels (peak at -60 vs. -180 min: 54.9+/-3.9 vs. 35.9+/-3.3 mmol/L; P < 0.05) to a reproducible extent, and these levels remained stable and within the normal range until 90 min. The mean GH concentration over 3 h (from -180 to 0 min) before ARG and/or GHRH was not modified by placebo or rhIGF-I. After placebo, the GH response to GHRH (peak, 23.6+/-2.9 microg/L) was strikingly enhanced (P < 0.05) by ARG coadministration (69.6+/-9.9 microg/L). rhIGF-I blunted the GH response to GHRH (13.1+/-4.5 microg/L; P < 0.05), whereas that to GHRH plus ARG was not modified (59.5+/-8.9 microg/L), although it occurred with some delay. Mean glucose and insulin concentrations were not modified by either placebo or rhIGF-I. In conclusion, ARG counteracts the inhibitory effect of rhIGF-I on somatotroph responsiveness to GHRH in humans. These findings suggest that the acute inhibitory effect of rhIGF-I on the GH response to GHRH takes place on the hypothalamus, possibly via enhancement of SS release, and that ARG overrides this action.

Concomitant impairment of growth hormone secretion and peripheral sensitivity in obese patients with obstructive sleep apnea syndrome.

To clarify the impairment of the GH/IGF-I axis in obstructive sleep apnea syndrome (OSAS), in 13 adult male patients with OSAS (OSA) as well as 15 weight-matched patients with simple obesity (OB) and 10 normal lean male subjects (NS), we studied: 1) the GH response to GHRH (1 micro g/kg iv) plus arginine (30 g iv); and 2) the IGF-I and IGF binding protein-3 responses to a very low dose recombinant human (rh)GH treatment (5.0 microg/kg sc per day for 4 d). The GH response to arginine plus GHRH in OSA was lower than in OB (P < 0.05), which in turn was lower than in NS (P < 0.001). Basal IGF-I levels in OSA were lower than in OB (P < 0.05), which in turn were lower than in NS (P < 0.03). As opposed to OB and NS, in OSA a very low rhGH dose did not affect IGF-I. Adjusting for age and basal values, rhGH-induced IGF-I rise in OSA was lower than in OB (P < 0.01). IGF binding protein-3, glucose, and insulin levels in the three groups were not modified by rhGH. OSA show a more marked impairment of the maximal secretory capacity of somatotroph cells together with reduced IGF-I sensitivity to rhGH stimulation. These findings suggest that OSAS is connoted by a concomitant impairment of GH secretion and sensitivity.

[Endocrine abnormalities in anorexia nervosa]. / Alterazioni endocrine nell'anoressia nervosa.

Anorexia nervosa is a syndrome with multifactorial etiology in which several genetic, biologic, psychological and social factors are involved. Patients affected by anorexia nervosa (AN) may develop multiple endocrine abnormalities, e.g. amenorrhea, hypothalamus-pituitary-adrenal axis hyperactivity, low T3 syndrome and peculiar changes of somatotroph axis function. These endocrine abnormalities are also found after prolonged starvation and may represent an adaptive response developed in order to save energy and proteins. It is still a matter of debate whether these endocrine changes are etiologic or secondary. In fact, several evidences suggest the existence in AN of hypothalamus functional alterations, which may be involved in the development and maintenance of the food intake disorder; on the other hand, the increased CRH secretion seems to be secondary to malnutrition as well as GH hypersecretion coupled to low IGF-I levels; the latter is a common finding in AN, as well as in other undernutrition and malabsorption conditions, type 1 diabetes mellitus, liver cirrhosis and catabolic states. Hypothalamic amenorrhea, which is one of the diagnostic criteria for AN, is not linked only to the reduction of body weight but reflects also deep alterations of gonadotropin secretory pattern. Low T3 syndrome is frequently found in AN; on the other hand, an iodide-induced hypothyroidism is quite uncommon. T3 reduction in AN seems to be an adaptive response to prolonged starvation; however the presence of a simultaneous central dysregulation cannot be excluded. Finally, AN patients frequently show defects in urinary concentration or dilution with inappropriate secretion of antidiuretic hormone, which may be due to intrinsic defects in the neurohypophysis or to abnormalities of its regulatory afferent neurons.