ACTA ENDOCRINOLOGICA (BUC)

The mechanism underlying anovulation in the polycystic ovary syndrome (PCOS) remains unclear, although an excessive number of small antral follicles at ultrasound scans and discrepancies with selected follicles sustain the hypothesis of altered follicular development. Anti-M?llerian (AMH) hormone is a member of TGF-b super family of growth factors produced by granulosa cells of pre- and small-antral follicle. The 2 to 3 fold increase in the number of growing follicles in the ovary from PCOS women is reflected by an increase in serum concentration of AMH and thus, this hormone may be a good marker of PCOS.\r\nAim. This study was intended to implement ultra-sensitive ELISA measurement of serum AMH from PCOS women and search for a potential correlation with clinical and laboratory parameters.\r\nSubjects and methods. Sera from patients with PCOS (n = 42) and control women (n = 22) were used for ELISA measurement of AMH (AMH-EIA, Beckman Coulter) with sensitivity of 0.7 pmol/L.\r\nResults. We found a serum concentration of AMH almost 3 folds higher in patients with PCOS compared to controls (73.7 ? 7.5 vs. 25.7 ? 3.9 pmol/L, P < 0.0001). Differences were even higher in lean subjects. A positive correlation was found between total testosterone and LH levels, but not with serum FSH or insulin. Moreover, AMH concentration was correlated to more hyperandrogenic PCOS and with amenorrhea, and thus to the severity of the syndrome.\r\nConclusion. Measurement of serum AMH may be used as a valuable marker for PCOS to confirm diagnosis and evaluate the extent of follicular dysfunction in relation with hyperandrogenism and menstrual disturbances.

A 63-years old patient with severe thyrotoxicosis with cachexia and high frequency atrial fibrillation showed an inadequate secretion of TSH. A pituitary macroadenoma was revealed by computed tomography. Acute octreotide administration decreased serum TSH\r\nfrom 2.48 mU/mL to 0.06 mU/mL and T3 from 3.1 ng/mL to normal values (0.93 ng/mL) in 3 days; at the same time serum T4 remained unchanged (raised).The response to octreotide supported the diagnosis of TSH-secreting adenoma. T3 suppression test is no longer useful at present for diagnosis.Administration of long- acting somatostatin analogues (lanreotide) together with antithyroid drugs (ATD) was initially necessary. However, after removal of pituitary tumor the clinical symptoms (including atrial fibrillation) disappeared.ATD administration was no longer necessary, nor was octreotide or lanreotide. Immunohistochemistry certified that the pituitary tumor was a pure thyrotropinoma (without plurihormonal expression). Complete cure of severe thyrotoxicosis due to a TSH-secreting pituitary adenoma by pituitary surgery is possible. Thyroidectomy is not indicated.

INTRODUCTION: Sleep apnea syndrome is a common manifestation of acromegaly. Although the obstructive type of apnea was thought to be predominant there are some reports suggesting that central apneic episodes show a high rate and are related to abnormalities of central respiratory control.\r\nAIM: The present study determines the presence and severity of central sleep apnea syndrome in patients with acromegaly compared with obese subjects.\r\nMATERIALS AND METHODS: 35 consecutive acromegalic patients (min GH (growth hormone) during oral glucose tolerance test (OGTT) 6.6 ng/ml) and 19 obese subjects (BMI=44 kg/m2) were polisomnographically recorded between 10 p.m and 6 a.m. Sleep and respiratory disturbances were manually staged according to standard criteria.\r\nRESULTS: The prevalence of sleep apnea syndrome in acromegaly group was 45.7% (16 out of 35 patients). The median of minimum GH level during OGTT was 8.3 ng/ml in apnea group and 5.16 ng/ml in nonapneic group (p>0.05). In acromegaly group with severe sleep apnea syndrome central apnea rate was greater than 10% in 6 out of 7 subjects with REM sleep and in 7 out of 10 with NREM sleep whereas in obesity group this percent was present in 6 out of 18 (REM sleep), respectively 7 out of 19 (NREM sleep).\r\nCONCLUSIONS: The study confirms the high prevalence of sleep apnea in acromegaly. GH serum level is not an indicator for the presence and severity of sleep apnea. Although the total time of central apnea per hour of sleep did not differ between the two groups, the percent (rate) of central apnea was significantly greater in acromegaly group.

Background: Germline aryl hydrocarbon receptor-interacting protein (AIP) mutations are found in familial isolated pituitary adenoma syndrome (FIPA) families and in a small number of sporadic pituitary adenoma (PA) patients. Although the tumorigenic mechanisms of AIP mutations are unclear, truncating mutations are considered pathogenic, but missense mutations are difficult to evaluate. p.R16H (c.47G>A) is a controversial AIP variant of unknown significance. Aim: To describe a new PA case associated with AIP p.R16H. Patients and methods: One AIP p.R16H non-functioning pituitary adenoma (NFPA) case identified by mutation sequencing screening of sporadic PA patients; 108 controls were screened for p.R16H. Results: The 38 yrs. old male NFPA patient had no family history of PA and harboured a heterozygous p.R16H variant. The proband and two brothers presented severe intellectual disability. Severe visual impairment was the initial symptom and clinical, biochemical and imaging examination demonstrated a large NFPA invading the right cavernous sinus. After transsphenoidal debulking, the remaining tumor continued growth. One of proband’s sisters was negative for p.R16H. Among controls, we identified one heterozygous p.R16H carrier, presenting a thyroid follicular neoplasm. Loss of heterozygosity analysis of the pituitary and thyroid tumors was not performed. Conclusions: We report two new occurrences of AIP p.R16H, associated with a NFPA and with a thyroid tumor. The NFPA patient was young and presented an invasive macroadenoma, features typical of AIP-mutated patients. Because the association between p.R16H and PAs has not been conclusively established, further research of p.R16H is warranted, in view of its implications for AIP genetic testing.

-

Vertebrate nonapeptide neurohormones constitute an evolutionarily conserved family, involved in vital functions, such as hydro-osmotic balance regulation, reproduction and social behaviour. Two human members of this family are known, vasopressin (AVP) and oxytocin (OXT), with their highly homologous genes closely located on Chr 20p13. Presence of vasotocin (AVT) in man has been suggested, but remains controversial, and genetic evidence is lacking. AVT activity could be explained by the presence of a third distinct gene for AVT or an RNA-processing mechanism involving products of AVP and/or OXT genes. To test the first hypothesis, we developed bioinformatics and experimental approaches using genomic DNA and fetal tissues mRNAs. Family-specific primers for AVT and neurophysin were designed based on CODEHOP strategy and used in our experiments. Results of bioinformatics and genomic DNA experiments (family-specific and Alu step-out PCR) suggest there is no evidence for an AVT gene in the genome. RNA-based techniques 3?-RACE and Family-Specific Domain Restriction Fragment RTPCR provided evidence for new transcript species that could code for AVT. Further experiments will be needed to characterize them. We discuss potential mechanisms of AVT mRNA generation based on AVP and OXT mRNAs, by alternative splicing, heterologous transsplicing or RNA-editing. While all methods we developed proved feasible, current results suggest there is no AVT gene in the genome, but specific mRNAs could be present in fetal tissues. Their full characterization may potentially allow identification of vasotocin mRNA and shed light on a subject of fundamental scientific interest.

IGF-I (Insulin like growth factor-I) plays a definitive role in the central nervous system (CNS) by modulating neuronal regeneration and survival. The local production of IGF-I in CNS has been demonstrated, but the contribution of circulating IGF-I transported through blood-brain barrier (BBB) has been just suggested in animals. There is currently no data available concerning IGF-I transport in CNS in humans. In order to investigate the passage of IGF-I over BBB in humans we have simultaneously measured the IGF-I and GH levels in serum and CSF in 25 patients with active acromegaly. IGF-I and GH levels in CSF were lower than in serum (2.2 ? 0.24 ng/mL vs 686.6 ? 46.83 ng/mL for IGF-I and 2.13 ? 0.627 mU/l vs 58.8 ? 15.86 mU/L for GH). However, both IGF-I and GH serum levels correlated with their CSF levels (r= 0.4, p<0.05 for IGF-I and r= 0.651, p= 0.006 for GH), suggesting that BBB is permeable for both hormones. In conclusion, we demonstrate the correlation of the IGF-I levels in serum and CSF, providing indirect evidence for IGF-I passage through BBB.