A genome-wide scan identifies mutations in the gene encoding phosphodiesterase 11A4 (PDE11A) in individuals with adrenocortical hyperplasia.

Phosphodiesterases (PDEs) regulate cyclic nucleotide levels. Increased cyclic AMP (cAMP) signaling has been associated with PRKAR1A or GNAS mutations and leads to adrenocortical tumors and Cushing syndrome. We investigated the genetic source of Cushing syndrome in individuals with adrenocortical hyperplasia that was not caused by known defects. We performed genome-wide SNP genotyping, including the adrenocortical tumor DNA. The region with the highest probability to harbor a susceptibility gene by loss of heterozygosity (LOH) and other analyses was 2q31-2q35. We identified mutations disrupting the expression of the PDE11A isoform-4 gene (PDE11A) in three kindreds. Tumor tissues showed 2q31-2q35 LOH, decreased protein expression and high cyclic nucleotide levels and cAMP-responsive element binding protein (CREB) phosphorylation. PDE11A codes for a dual-specificity PDE that is expressed in adrenal cortex and is partially inhibited by tadalafil and other PDE inhibitors; its germline inactivation is associated with adrenocortical hyperplasia, suggesting another means by which dysregulation of cAMP signaling causes endocrine tumors.

Modulatory role of the ovarian function in neuroimmunoendocrine axis activity.

The aim of this study was to evaluate the effect of ovariectomy on the acute-phase response of inflammatory stress. Ex vivo adrenocortical, peripheral mononuclear cell (PMNC) and adipocyte activities were studied in intact and ovariectomized mice. Endotoxemia was mimicked by intraperitoneal administration of bacterial lipopolysaccharide (LPS; 25 mg per mouse) to sham-operated and 21-day ovariectomized mice. Circulating corticosterone, tumor necrosis factor-α (TNFα) and leptin concentrations were monitored before and 30-120 min after the administration of LPS. Additionally, in vitro experiments were performed with isolated corticoadrenal cells, PMNCs and omental adipocytes from sham-operated and ovariectomized mice incubated with specific secretagogues. The results indicate that while ovariectomy enhanced TNFα secretion after in vivo administration of LPS, it reduced corticoadrenal response and abrogated LPS-elicited leptin secretion into the circulation. While the corticoadrenal sensitivity to ACTH stimulation was reduced by ovariectomy, the LPS-induced PMNC response was not affected. Exogenous leptin enhanced baseline PMNC function regardless of surgery. Finally, ovariectomy drastically reduced in vitro adipocyte functionality. Our data support the notion that ovariectomy modified neuroendocrine-immune-adipocyte axis function and strongly suggest that ovarian activity could play a pivotal role in the development of an adequate immune defense mechanism after injury.

Enhanced proinflammatory cytokine response to bacterial lipopolysaccharide in the adult male rat after either neonatal or prepubertal ablation of biological testosterone activity.

A sex steroid-dependent modulation of the immune function in mammals is accepted, and evidence suggests that while estrogens enhance, androgens inhibit the immune response. The aim of this study was to explore in the adult male rat the effect of either neonatal flutamide (FTM) treatment or prepubertal orchidectomy (ODX) on endocrine markers in the basal condition and peripheral tumor necrosis factor alpha (TNFα) levels during inflammatory stress. For these purposes, (1) 5-day-old male rats were subcutaneously injected with either sterile vehicle alone or containing 1.75 mg FTM, and (2) 25-day-old male rats were sham operated or had ODX. Rats were sacrificed (at 100 days of age) in the basal condition for determination of peripheral metabolite levels. Additional rats were intravenously injected with bacterial lipopolysaccharide (LPS; 25 µg/kg body weight, i.v.) and bled for up to 4 h. Data indicate that (1) ODX increased peripheral glucocorticoid levels and reduced those of testosterone, whereas FTM-treated rats displayed low circulating leptin concentrations, and (2) LPS-induced TNFα secretion in plasma was significantly enhanced in the FTM and ODX groups. Our study supports that neonatal FTM treatment affected adiposity function, and adds data maintaining that androgens have a suppressive role in proinflammatory cytokine release in plasma during inflammation.

Prolonged but not short negative energy condition restored corticoadrenal leptin sensitivity in the hypothalamic obese rat.

BACKGROUND/AIM: We have reported that neonatal treatment with monosodium L-glutamate (MSG), which causes damage to the arcuate nucleus, leads to severe hyperleptinemia and reduced adrenal leptin receptor (ob-Rb) expression in adulthood. As a result, rats given MSG neonatally display corticoadrenal leptin-resistance, a defect that is overridden by normalization of corticoadrenal hyperfunction. The aim of the present study was to determine whether negative energy conditions could correct corticoadrenal cell dysfunction in rats given MSG neonatally. METHODS: Normal (CTR) and MSG-treated female rats were subjected to food removal for 1-5 days, or prolonged (24-61 days) food restriction (FR). Plasma levels of several biomarkers and in vitro corticoadrenal function were evaluated following starvation or FR. RESULTS: Fasting for 1-5 days reduced plasma leptin levels in CTR and MSG rats, compared to levels in the respective groups fed ad libitum(p < 0.05), but adrenal leptin-resistance was unchanged. With prolonged FR, isolated adrenal cells from MSG rats became sensitive to leptin, which lowered ACTH-induced glucocorticoid release. This restoration of leptin response was associated with normalization of adrenal ob-Rb gene expression. CONCLUSION: Dietary restriction in some leptin-resistant obese phenotypes may normalize adrenocortical function.

Insulin modulation of luteinizing hormone secretion in normal female volunteers and lean polycystic ovary syndrome patients.

BACKGROUND/AIMS: Endocrine features of polycystic ovary syndrome (PCOS) include altered ovarian steroidogenesis, hyperinsulinemia and abnormal luteinizing hormone (LH) secretion. This study was undertaken to further evaluate the role of insulin to modulate LH secretion in lean PCOS patients with normal insulin sensitivity and normal volunteers. METHODS: The study was performed in five nonobese patients diagnosed with PCOS on the basis of amenorrhea and a polycystic morphology at ovarian ultrasound, and 5 normal controls in early to mid-follicular phase and matched for weight and age. All subjects were phenotyped, and then admitted for 12 h of frequent (q 10') blood sampling on two separate occasions, once for a baseline study and the other time for a hyperinsulinemic and euglycemic clamp study. LH was measured in samples obtained throughout each admission in order to perform LH pulse analysis. RESULTS: Baseline LH secretion in PCOS subjects was significantly different from controls: they had higher LH levels, higher LH/FSH ratios as well as a faster LH pulse frequency than normal women. Insulin administration did not affect the pattern of LH secretion of PCOS patients, whereas it significantly increased the LH pulse frequency while decreasing the LH interpulse intervals in the controls. CONCLUSIONS: These data confirm that an abnormal pattern of LH secretion characteristic of PCOS can be observed in lean patients, and appears independent of peripheral insulin levels. Furthermore, our results in lean controls provide the first direct evidence that peripheral insulin can modulate the activity of hypothalamic gonadotropin-releasing hormone (GnRH) neurons in the human.

Neuroendocrine, metabolic, and immune functions during the acute phase response of inflammatory stress in monosodium L-glutamate-damaged, hyperadipose male rat.

In rats, neonatal treatment with monosodium L-glutamate (MSG) induces several metabolic and neuroendocrine abnormalities, which result in hyperadiposity. No data exist, however, regarding neuroendocrine, immune and metabolic responses to acute endotoxemia in the MSG-damaged rat. We studied the consequences of MSG treatment during the acute phase response of inflammatory stress. Neonatal male rats were treated with MSG or vehicle (controls, CTR) and studied at age 90 days. Pituitary, adrenal, adipo-insular axis, immune, metabolic and gonadal functions were explored before and up to 5 h after single sub-lethal i.p. injection of bacterial lipopolysaccharide (LPS; 150 microg/kg). Our results showed that, during the acute phase response of inflammatory stress in MSG rats: (1) the corticotrope-adrenal, leptin, insulin and triglyceride responses were higher than in CTR rats, (2) pro-inflammatory (TNFalpha) cytokine response was impaired and anti-inflammatory (IL-10) cytokine response was normal, and (3) changes in peripheral estradiol and testosterone levels after LPS varied as in CTR rats. These data indicate that metabolic and neroendocrine-immune functions are altered in MSG-damaged rats. Our study also suggests that the enhanced corticotrope-corticoadrenal activity in MSG animals could be responsible, at least in part, for the immune and metabolic derangements characterizing hypothalamic obesity.

Metformin inhibits adenosine 5'-monophosphate-activated kinase activation and prevents increases in neuropeptide Y expression in cultured hypothalamic neurons.

The oral antidiabetic agent metformin acts at least partially via an activation of AMP-activated kinase (AMPK) in liver and muscle cells. It has appeared recently that hypothalamic AMPK is a key regulator of feeding in mammals. Because metformin also exhibits anorectic effects in animal models as well as in humans, we hypothesized that AMPK may be a target of metformin in hypothalamic neurons. In this study, we show that, in primary cultures of rat hypothalamic neurons, low glucose levels stimulate the phosphorylation of AMPK, thus increasing neuropeptide Y (NPY) gene expression. The addition of metformin in low glucose conditions was found to block AMPK phosphorylation. Consistently, the stimulation of NPY observed in low glucose conditions was also inhibited by the drug. Proopiomelanocortin gene expression measured in parallel was inhibited under low glucose conditions, but in contrast to NPY, it was not dependent upon AMPK and not affected by metformin. Taken together, our data demonstrate that metformin can inhibit AMPK activity in hypothalamic neurons, thus modulating the expression of the orexigenic peptide NPY. These results provide, for the first time, a potential mechanism of action for the anorectic effects of metformin, a widely used drug that could represent a valuable adjunct to novel therapies aimed at modulating central feeding pathways.

Genetics of carney triad: recurrent losses at chromosome 1 but lack of germline mutations in genes associated with paragangliomas and gastrointestinal stromal tumors.

CONTEXT: Carney triad (CT) describes the association of paragangliomas (PGLs) with gastrointestinal stromal tumors (GISTs) and pulmonary chondromas. Inactivating mutations of the mitochondrial complex II succinate dehydrogenase (SDH) enzyme subunits SDHB, SDHC, and SDHD are found in PGLs, gain-of-function mutations of c-kit (KIT), and platelet-derived growth factor receptor A (PDGFRA) in GISTs. OBJECTIVE: Our objective was to investigate the possibility that patients with CT and/or their tumors may harbor mutations of the SDHB, SDHC, SDHD, KIT, and PDGFRA genes and identify any other genetic alterations in CT tumors. DESIGN: Three males and 34 females with CT were studied retrospectively. We sequenced the stated genes and performed comparative genomic hybridization on a total of 41 tumors. RESULTS: No patient had coding sequence mutations of the investigated genes. Comparative genomic hybridization revealed a number of DNA copy number changes: losses dominated among benign lesions, there were an equal number of gains and losses in malignant lesions, and the average number of alterations in malignant tumors was higher compared with benign lesions. The most frequent and greatest contiguous change was 1q12-q21 deletion, a region that harbors the SDHC gene. Another frequent change was loss of 1p. Allelic losses of 1p and 1q were confirmed by fluorescent in situ hybridization and loss-of-heterozygosity studies. CONCLUSIONS: We conclude that CT is not due to SDH-inactivating or KIT- and PDGFRA-activating mutations. GISTs and PGLs in CT are associated with chromosome 1 and other changes that appear to participate in tumor progression and point to their common genetic cause.

Hypogonadism in a patient with a mutation in the luteinizing hormone beta-subunit gene.

A 30-year-old man who presented with delayed puberty and infertility was found to have hypogonadism associated with an absence of circulating luteinizing hormone. The patient had a homozygous missense mutation in the gene that encodes the beta subunit of luteinizing hormone (Gly36Asp), a mutation that disrupted a vital cystine knot motif and abrogated the heterodimerization and secretion of luteinizing hormone. Treatment with human chorionic gonadotropin increased circulating testosterone, promoted virilization, and was associated with the appearance of normal spermatozoa in low concentrations. This case illustrates the important physiological role that luteinizing hormone plays in male sexual maturation and fertility.

Impairment in insulin sensitivity after early androgenization in the post-pubertal female rat.

A link is known to exist between hyperandrogenicity and insulin resistance in mammals. We explored whether androgenization, early in reproductive life, in the female rat has any impact on later peripheral insulin sensitivity and parametrial (PM) fat function. Female, 60 day-old, rats were injected (i.m.) with 100 mul of sterile corn oil either alone (CT) or containing 2 mg of testosterone propionate (TP); rats were then used for experimentation at age 120 days. Daily food intake and body weight were recorded. Different groups of CT and TP rats were subjected to a high glucose load test or 24 h fasting for evaluation of changes in circulating levels of several metabolites and body composition. In vitro experiments were run to study the impact of androgenization on isolated PM adipocyte response to insulin. Finally, the direct effect of testosterone on insulin-induced leptin secretion by normal PM adipocytes was also evaluated. Androgenization induced a significant increase in daily food intake and body weight for the first 20 days after treatment. In vivo experiments indicate that TP rats released more (P<0.05) insulin than CT animals after high glucose load in order to maintain similar circulating glucose levels, a characteristic accompanied by decreased (P<0.05) overall corticoadrenal response in TP rats. Several metabolic responses to fasting were similar in both groups, although impaired adrenal response and changes in body composition were observed only in TP rats. Interestingly, cultured PM adipocytes from TP rats were less (P<0.05) sensitive than CT cells to insulin-induced leptin secretion. Also, we found that 48 h exposure of normal PM adipocytes to high testosterone concentration also impaired adipocyte endocrine function. Our study strongly supports that development of insulin resistance, in the female gender, can be established after an early, even transient, hyperandrogenemia.

Effects of cytokines on gonadotropin-releasing hormone (GnRH) gene expression in primary hypothalamic neurons and in GnRH neurons immortalized conditionally.

Various cytokines produced during the immune reaction can modulate the neuroendocrine reproductive axis, probably by inducing changes in the activity of hypothalamic GnRH neurons. However, the precise cellular and molecular effects of cytokines on these neurons have not been reported yet. To gain a better insight into these regulations, we first examined the pattern of expression of cytokine receptors in a novel neuronal cell line expressing GnRH (Gnv-4 cells). Among others, gp130 is expressed in Gnv-4 cells, together with the ligand receptor subunits specific for IL-6 as well as oncostatin M (OSM). Consistent with the latter observation, we show that OSM stimulates the expression of the immediate early genes c-fos and early growth response-1 in Gnv-4 cells, an effect dependent upon the activation of the MAPK Erk1/2 intracellular signaling pathway. Functional studies performed in parallel in Gnv-4 cells and in primary hypothalamic neuronal cell cultures show that OSM, although devoid of any effect of its own on GnRH gene expression, can inhibit dose-dependently the stimulation of GnRH expression by N-methyl-d-aspartic acid. In conclusion, these data demonstrate that a GnRH-expressing neuronal cell line can be modulated in vitro by cytokines implicated in the regulation of the reproductive axis. Moreover, they provide the first evidence of an involvement of OSM in these regulations.

Gonadotropin-releasing hormone-expressing neurons immortalized conditionally are activated by insulin: implication of the mitogen-activated protein kinase pathway.

Energy balance exerts a critical influence on reproduction via changes in the circulating levels of hormones such as insulin. This modulation of the neuroendocrine reproductive axis ultimately involves variations in the activity of hypothalamic neurons expressing GnRH. Here we studied the effects of insulin in primary hypothalamic cell cultures as well as a GnRH neuronal cell line that we generated by conditional immortalization of adult hypothalamic neurons. These cells, which represent the first successful conditional immortalization of GnRH neurons, retain many of their mature phenotypic characteristics. In addition, we show that they express the insulin receptor. Consistently, their stimulation with insulin activates both the phosphatidylinositol 3-kinase and the Erk1/2 MAPK signaling pathways and stimulates a rapid increase in the expression of c-fos, demonstrating their responsiveness to this hormone. Further work performed in parallel in immortalized GnRH-expressing cells and primary neuronal cultures containing non-GnRH-expressing neurons shows that insulin induces the expression of GnRH in both models. In primary cultures, inhibition of the Erk1/2 pathway abolishes the stimulation of GnRH expression by insulin, whereas blockade of the phosphatidylinositol 3-kinase pathway has no effect. In conclusion, these data strongly suggest that GnRH neurons are directly sensitive to insulin and implicate for the first time the MAPK Erk1/2 signaling pathway in the central effects of insulin on the neuroendocrine reproductive axis.

Functional genomics approaches for the study of sporadic adrenal tumor pathogenesis: clinical implications.

Although sporadic adrenal tumors are frequently encountered in the general population their pathogenesis is not well elucidated. The advent of functional genomics/bioinformatics tools enabling large scale comprehensive genome expression profiling should contribute to significant progress in this field. Some studies have already been published describing gene expression profiles of benign and malignant adrenocortical tumors and phaeochromocytomas. Several genes coding for growth factors and their receptors, enzymes involved in steroid hormone biosynthesis, genes related to the regulation of cell cycle, cell proliferation, adhesion and intracellular metabolism have been found to be up- or downregulated in various tumors. Some alterations in gene expression appear so specific for certain tumor types that their application in diagnosis, determination of prognosis and the choice of therapy can be envisaged. In this short review, the authors will present a synopsis of these recent findings that seem to open new perspectives in adrenal tumor pathogenesis, with emphasis on changes in steroidogenic enzyme expression profiles and highlighting possible clinical implications.

Apoplexy in pituitary macroadenoma: eight patients presenting in 12 months.

Pituitary apoplexy is an ill-defined clinical entity. Some authors include hypoxic pituitary infarction, even in the absence of tumor after hemorrhagic delivery, whereas others apply this term strictly to hemorrhage within a pituitary adenoma. We conducted the present study to establish the prevalence, clinical characteristics, and outcome of pituitary apoplexy, defined as an endocrine crisis characterized by acute intense headache, with or without altered consciousness, rapid development of visual or motor ocular disorders, and pituitary failure, associated with a large pituitary adenoma. We describe 8 consecutive patients (1 woman and 7 men, aged 29-66 yr) presenting over 12 months with pituitary apoplexy. We reviewed patient charts for symptoms, imaging characteristics, hormonal data, management, pathologic findings, and outcome. We examined our pituitary tumors database for cases of macroadenoma without apoplexy occurring during the same period. In 5 patients, potential precipitating factors were present. In 6 patients (3 nonsecreting tumors, 1 free-alpha-subunit-secreting tumor, 1 growth hormone and prolactin-secreting tumor with acromegaly, and 1 prolactinoma), no pituitary disease was suspected before the acute event, representing 19% of newly diagnosed pituitary macroadenomas during the same period of time, a higher proportion than expected from our previously published series. The 2 other patients had known pituitary macroadenomas, a nonsecreting tumor and a prolactinoma on dopamine agonist therapy. Pituitary insufficiency at diagnosis included adrenal failure in 4 patients. Transsphenoidal tumor removal was performed 3-9 days after the onset of symptoms (mean, 5.3 d) in 7 of the 8 patients. Pathologic analysis disclosed tumor hemorrhage in 4 cases, ischemic necrosis in 2, and ischemia after intrasellar hemorrhage in 1. Preoperative magnetic resonance imaging was more sensitive than computed tomography for identifying hemorrhage. The newly diagnosed prolactinoma was treated with dopamine agonist. Complete neuro-ophthalmic recovery was observed in all cases, but only 2 patients displayed normal pituitary function on follow-up. The other 6 patients required long-term hormone replacement therapy. These data show that early surgical decompression prevents persistent neuro-ophthalmic deficit, but does not prevent persistent pituitary insufficiency. Moreover, published data indicate that the efficacy of surgery for the relief of neuro-ophthalmic symptoms decreases with increasing syndrome duration. Our data confirm that apoplexy occurs most often as the inaugural manifestation of pituitary macroadenoma, and suggest a recent increase of cases of apoplexy in our area.

The neuropeptide Y Y1 receptor mediates NPY-induced inhibition of the gonadotrope axis under poor metabolic conditions.

Hypothalamic neuropeptide Y (NPY) plays a central role in the control of food intake, energy balance, and modulation of neuroendocrine functions. In particular, an increase in NPY expression participates in the inhibition of the reproductive activity under poor nutritional conditions. The present study was designed to evaluate further the involvement of the Y1 subtype of NPY receptors in these effects. Food intake, body weight gain, and the onset of puberty were studied in groups of wild-type and Y1 deficient mice that were either fed ad libitum or subjected to a 30% restriction in food intake. This moderate feeding restriction induced a similar deficit in body weight gain in wild-type and in Y1 knockout mice. However, although wild-type mice experienced the expected delay of puberty, all mice in the food restriction group and lacking Y1 could go through puberty over the time of the experiment despite decreases in circulating leptin levels and increases in hypothalamic NPY expression. This observation demonstrates that the absence of Y1 impairs the perception of decreasing energy stores by the gonadotrope axis, demonstrating a physiological role for Y1 in the sensing of endogenous metabolic parameters by the hypothalamus.

The neuropeptide Y Y1 receptor regulates leptin-mediated control of energy homeostasis and reproductive functions.

The orexigenic neurotransmitter neuropeptide Y (NPY) plays a central role in the hypothalamic control of food intake and energy balance. NPY also exerts an inhibition of the gonadotrope axis that could be important in the response to poor metabolic conditions. In contrast, leptin provides an anorexigenic signal to centrally control the body needs in energy. Moreover, leptin contributes to preserve adequate reproductive functions by stimulating the activity of the gonadotrope axis. It is of interest that hypothalamic NPY represents a primary target of leptin actions. To evaluate the importance of the NPY Y1 and Y5 receptors in the downstream pathways modulated by leptin and controlling energy metabolism as well as the activity of the gonadotrope axis, we studied the effects of leptin administration on food intake and reproductive functions in mice deficient for the expression of either the Y1 or the Y5 receptor. Furthermore, the role of the Y1 receptor in leptin resistance was determined in leptin-deficient ob/ob mice bearing a null mutation in the NPY Y1 locus. Results point to a crucial role for the NPY Y1 receptor in mediating the NPY pathways situated downstream of leptin actions and controlling food intake, the onset of puberty, and the maintenance of reproductive functions.

Gonadotropin-releasing hormone secretion from hypothalamic neurons: stimulation by insulin and potentiation by leptin.

Insulin and leptin are peripheral metabolic factors signaling the body needs in energy to the central nervous system. Because energy homeostasis and reproductive function are closely related phenomena, we investigated the respective roles played by insulin and leptin in the hypothalamic control of GnRH secretion. We observed that increasing circulating insulin levels, by performing hyperinsulinemic clamp studies in male mice, was associated with a significant rise in LH secretion. This effect of insulin is likely mediated at the hypothalamic level, because it was also found to stimulate the secretion and the expression of GnRH by hypothalamic neurons in culture. Leptin was found to potentiate the effect of insulin on GnRH secretion in vitro but was devoid of any effect on its own. These data represent the first evidence of direct insulin sensing by hypothalamic neurons involved in activating the neuroendocrine gonadotrope axis. They also demonstrate that these neurons can integrate different hormonal signals to modulate net hypothalamic GnRH output. We propose that such integration is an essential mechanism for the adaptation of reproductive function to changes in the metabolic status of an individual.

Progressive onset of adrenal insufficiency and hypogonadism of pituitary origin caused by a complex genetic rearrangement within DAX-1.

DAX-1 [dosage-sensitive sex reversal, adrenal hypoplasia congenital (AHC) critical region on the X chromosome, gene 1] is a transcription factor expressed in the adrenal gland and at all levels of the gonadotrope axis. Inactivating mutations of DAX1 result in the X-linked form of AHC with associated hypogonadotropic hypogonadism. AHC usually reveals itself as adrenal failure in early infancy, although a wide range of phenotypic expression has been reported. We describe a patient who was diagnosed with adrenal failure at 6 wk of age, but who experienced recovery of adrenal function of several months' duration later in infancy. He subsequently failed to undergo puberty because of hypogonadotropic hypogonadism of pituitary origin, and he was also diagnosed with schizophrenia in early adulthood. Molecular genetic analyses revealed a complex rearrangement in DAX1, including a 2.2-kb deletion spanning the entire second exon and a small 27-bp insertion. The putative protein encoded by this mutated gene is 429 amino acids long. The initial 389 residues probably correspond to the wild-type DAX-1 sequence, whereas the last 40 amino acids are presumably completely unrelated, being transcribed from the intronic sequence adjacent to exon 1. In vitro functional analyses confirm the absence of repressor activity exerted by such mutant protein. These studies expand the genotypic and phenotypic spectrum of DAX-1 insufficiency in humans.

Pharyngeal pituitary non-functioning adenoma with normal intra-sellar gland: massive tumor shrinkage on octreotide therapy.

OBJECTIVE: Functioning or non-functioning ectopic tumors may develop from pharyngeal pituitary remnants. They constitute <1% of all obstructive pharyngeal masses and they have a strong tendency to bleed. We report a case of a non-functioning ectopic pituitary adenoma of the rhino-pharynx studied over a long-term somatostatin analog treatment. PATIENT AND TREATMENT: A 60-Year-old woman presented with severe posterior epistaxis. She had complained of nasal obstruction for the past 2 Years. Magnetic resonance imaging (MRI) and endoscopic examination revealed a 2 cm exophytic, bleeding mass in the cavum, which was judged inoperable, and a biopsy was performed. On immunostaining, tumor cells were positive for pancytokeratins MNF 116 and C11, epithelial membrane antigen, chromogranin and neuron-specific enolase (NSE), and negative for synaptophysin, desmin, actin, estrogen and progesterone receptors, all anterior pituitary hormones and human chorionic gonadotropin. Blood levels of the above hormones and tumor markers were normal, except for a moderate elevation of NSE (33.8 microg/l, normal value <12 microg/l). It was concluded that this was a non-functioning pituitary adenoma of the rhino-pharynx. MRI showed a normal intra-sellar pituitary gland, including the normal bright signal of the posterior lobe. Somatostatin receptor scintigraphy (SRS) disclosed intense tracer uptake in the tumor, indicating high somatostatin receptor content. There was also an intense uptake in the intra-sellar pituitary. Therapy with long-acting octreotide was started, 20 mg per Month i.m. RESULTS: The patient has been on octreotide for the last 12 Months. Nasal obstruction rapidly subsided and bleeding did not recur. Repeated endoscopic examinations showed rapid tumor reduction, the mass shrinkage being almost complete at 3 Months. This was confirmed by MRI, while SRS showed markedly decreased uptake in the residual tumor and the intra-sellar pituitary, and NSE became normal. CONCLUSION: Pharyngeal pituitary remnant adenomas are rare, but they must be considered in the differential diagnosis of bleeding or obstructive masses of the rhino-pharynx. In this case, the positive SRS influenced the choice of octreotide, as an alternative to surgery. As we show for the first time in this location, octreotide can exert prolonged and marked anti-tumoral effects in non-functioning adenoma.

Neonatal hypothalamic androgenization in the female rat induces changes in peripheral insulin sensitivity and adiposity function at adulthood.

UNLABELLED: It is recognized that there exists a link between hyperandrogenicity and insulin resistance. OBJECTIVE: By using the neonatally androgenized female rat we explored whether this treatment modifies peripheral insulin sensitivity and visceral fat function at adulthood. EXPERIMENTAL DESIGNS: On day 5 of age, female Sprague-Dawley pups were injected, sub cutaneous, with either 50 ml of sterile corn oil alone (CT) or containing 1.25 mg of testosterone propionate (TP) and further used for experimentation on day 100 of age. CT and TP rats were killed by decapitation in non-fasting condition and blood samples were kept frozen for measurement of different metabolites. Immediately after sacrifice, freshly dissected visceral fat pads were used for isolation of adipocytes, these cells were then incubated with medium alone or containing different concentrations of insulin in order to determine leptin secreted into the medium. Additionally, in vivo metabolic responses to intravenous high glucose load were performed in, 24 hour-fasting, CT and TP rats. RESULTS: We found that neonatal androgenization induced adult animals displaying higher visceral adiposity mass, body weight and leptinemia than CT rats. No group differences were found in basal circulating levels of several hormones and metabolic parameters. The results of the high glucose load 90-min test indicated that TP and CT rats developed similar glycemia but this accounted because of an early significantly higher peak values of circulating insulin in TP than in CT rats, regardless of similar enhancement in circulating glucocorticoid concentrations in both groups. While high glucose load significantly increased, over the baseline, circulating leptin concentrations as early as 30 min post-glucose in CT rats, in TP animals, it significantly enhanced leptinemia only by the end of the test. Finally, results of in vitro incubations of isolated visceral adipocytes indicated that cells from androgenized rats spontaneously released more leptin than control cells, although they were less responsive than CT cells to insulin-induced leptin output. CONCLUSION: Our study strongly supports the hypothesis that development of insulin resistance seems to be dependent on early hyperandrogenicity.