Adrenocorticotropic Hormone Secretion Research Articles

Unusual ectopic ACTH syndrome in a patient with orbital neuroendocrine tumor, resulted false-positive outcome of BIPSS:a case report

BackgroundCushing’s syndrome has been described as a complex endocrine disorder characterized with high cortisol concentration. Correct and early diagnosis of Cushing’s syndrome is challenging. According to the latest guideline, bilateral inferior petrosal sinus sampling (BIPSS) is considered to be the gold standard for the differential diagnosis. However, in some unusual cases, this method may be false positive. Here, we presented a rare case of orbital neuroendocrine tumor secreting adrenocorticotrophic hormone with false positive inferior petrosal sinus sampling.Case presentationA 48-year-old woman was admitted to West China Hospital of Sichuan University, presenting with fatigue, whole body edema for 1 year, alopecia and skin pigmentation for 5 months. Hormonal profiles including plasma cortisol and adrenocorticotrophic hormone (ACTH) measurements and low-dose dexamethasone inhibition test suggested that the patient had Cushing’s syndrome. However, during tumor location phase, the results of high-dose dexamethasone inhibition test (HDDST) contradicted desmopressin (DDAVP) stimulation test. Thus, BIPSS was employed, and its results indicated a pituitary origin. Interestingly, MRI of sellar region showed an innocent pituitary but caught a serendipitous lesion in the lateral rectus muscle of left eye, which was later proved to be an orbital neuroendocrine tumor secreting ACTH by pathological and immunohistochemical results. ACTH level of the patients was < 0.1 ng/L and cortisol level was 51.61 nmol/L 1 week after surgery. At 24 months follow-up, the patient appeared stable with no complaints nor any symptoms of Cushing’s syndrome, including moon face, purple striate and central obesity. The patient’s life quality also improved significantly.ConclusionWe reported a rare case of endogenous Cushing’s syndrome due to ectopic ACTH secreting from an orbital neuroendocrine tumor. This unique case of orbital EAS suggests that orbital venous blood backflow, owning to abnormal anatomic structures, may possibly lead to false positive BIPSS results.

Vasopressin gene products are colocalised with corticotrophin-releasing factor within neurosecretory vesicles in the external zone of the median eminence of the Japanese macaque monkey (Macaca fuscata).

Arginine vasopressin (AVP), when released into portal capillaries with corticotrophin-releasing factor (CRF) from terminals of parvocellular neurones of the hypothalamic paraventricular nucleus (PVH), facilitates the secretion of adrenocorticotrophic hormone (ACTH) in stressed rodents. The AVP gene encodes a propeptide precursor containing AVP, AVP-associated neurophysin II (NPII), and a glycopeptide copeptin, although it is currently unclear whether copeptin is always cleaved from the neurophysin and whether the NPII and/or copeptin have any functional role in the pituitary. Furthermore, for primates, it is unknown whether CRF, AVP, NPII and copeptin are all colocalised in neurosecretory vesicles in the terminal region of the paraventricular CRF neurone axons. Therefore, we investigated, by fluorescence and immunogold immunocytochemistry, the cellular and subcellular relationships of these peptides in the CRF- and AVP-producing cells in unstressed Japanese macaque monkeys (Macaca fuscata). Reverse transcription-polymerase chain reaction analysis showed the expression of both CRF and AVP mRNAs in the monkey PVH. As expected, in the magnocellular neurones of the PVH and supraoptic nucleus, essentially no CRF immunoreactivity could be detected in NPII-immunoreactive (AVP-producing) neurones. Immunofluorescence showed that, in the parvocellular part of the PVH, NPII was detectable in a subpopulation (approximately 39%) of the numerous CRF-immunoreactive neuronal perikarya, whereas, in the outer median eminence, NPII was more prominent (approximately 52%) in the CRF varicosities. Triple immunoelectron microscopy in the median eminence demonstrated the presence of both NPII and copeptin immunoreactivity in dense-cored vesicles of CRF-containing axons. The results are consistent with an idea that the AVP propeptide is processed and NPII and copeptin are colocalised in hypothalamic-pituitary CRF axons in the median eminence of a primate. The CRF, AVP and copeptin are all co-packaged in neurosecretory vesicles in monkeys and are thus likely to be co-released into the portal capillary blood to amplify ACTH release from the primate anterior pituitary.

Liver metastases from pituitary carcinomas mimicking visceral well-differentiated neuroendocrine tumors: a series of four cases

BackgroundPathologists frequently encounter neuroendocrine tumors (NETs) presenting as multiple liver masses in routine practice. Most often, these are well-differentiated tumors with characteristic histologic features. In contrast, pituitary carcinoma is very rare, and there is limited data on its natural history and pathologic characterization.MethodsThe aim of this study was to describe clinical characteristics, histomorphology, immunophenotype and follow-up of pituitary carcinoma involving the liver and mimicking well-differentiated NETs of visceral origin. We selected a group of well-differentiated NETs of the pancreas to use as immunophenotypic controls. We identified 4 patients (age range, 51 to 73) with pituitary corticotroph carcinoma with liver metastases. Three patients presented with Cushing syndrome.ResultsAll cases histologically resembled well-differentiated NETs of visceral origin with Ki-67 proliferation indices of 5–42% and expression of T-PIT; metastatic tumors were not immunoreactive with CDX2, Islet 1 or TTF-1.ConclusionsFrequently, these cases display adrenocorticotropic hormone (ACTH) secretion and pituitary-specific transcription factor immunohistochemistry may be used as a reliable marker to distinguish metastatic pituitary carcinoma from NETs of visceral origin in addition to delineating a corticotroph carcinoma from somatotroph, lactotroph, thyrotroph, and gonadotroph lineage. Although rare, the differential diagnosis of pituitary carcinoma should be considered in metastatic well-differentiated NETs in which the site of origin is uncertain. In summary, pituitary corticotroph carcinoma can metastasize to the liver and mimic well-differentiated NET.

Circulating Plasma microRNA to Differentiate Cushing's Disease From Ectopic ACTH Syndrome.

Corticotropinomas and adrenocorticotropic hormone (ACTH)-secreting neuroendocrine tumors exhibit differential levels of some microRNAs (miRs) compared to normal tissue. Because miRs can be released from tissues into circulation, they offer promise as novel disease biomarkers.Objective: To evaluate whether miRs are differentially detected in plasma samples of patients with ACTH-dependent Cushing's syndrome (CS).Design: Case-control study.Methods: Morning fasting plasma samples were collected from 41 consecutive patients with confirmed ACTH-dependent CS and 11 healthy subjects and stored at −80°C. Twenty-one miRs previously reported to be differentially expressed in ACTH-secreting tumors vs. healthy tissue samples were quantified in plasma by qPCR.Results: Among enrolled subjects, 28 were confirmed to have Cushing's disease (CD), 13 had ectopic ACTH secretion (EAS) and 11 were healthy controls. We found statistically significant differences in the circulating levels of miR-16-5p [45.04 (95% CI 28.77–61.31) in CD vs. 5.26 (2.65–7.87) in EAS, P < 0.001; q = 0.001], miR-145-5p [0.097 (0.027–0.167) in CD vs. undetectable levels in EAS, P = 0.008; q = 0.087] and differences in miR-7g-5p [1.842 (1.283–2.400) in CD vs. 0.847 (0.187–1.507) in EAS, P = 0.02; q = 0.14]. The area under the receiver-operator (ROC) curve was 0.879 (95% CI 0.770–0.987), p < 0.001, when using miR-16-5p to distinguish between CD and EAS. Circulating levels of miR-16-5p in the healthy control group differed from that of both the CD and EAS groups.Conclusions: Plasma miR levels differ in patients with CD and EAS. In particular, miR-16-5p, miR-145-5p and miR-7g-5p are promising biomarkers for further research to differentiate ACTH-dependent CS.

Surgical outcomes and multidisciplinary management strategy of Cushing's disease: a single-center experience in China.

The primary aim of this study was to investigate the value of multidisciplinary team (MDT) management in treating patients with Cushing's disease (CD). The secondary aim was to assess the concordance of bilateral inferior petrosal sinus sampling (BIPSS) lateralization with intraoperative observations. The authors recruited 124 consecutive patients (128 procedures) who had undergone endoscopic endonasal resection of adrenocorticotropic hormone-secreting pituitary adenomas from May 2014 to April 2018 and assessed their clinical characteristics, surgical outcomes, and adjuvant therapies. The criteria for surgical remission were normalized serum and urinary cortisol levels, which could be suppressed by a low-dose dexamethasone suppression test at 3-months' follow-up without adjuvant treatment. The remission rates of the 113 patients with long-term follow-up (20.3 ± 12.2 months) were 83.2% after surgery alone and 91.2% after adjuvant therapy. The surgical remission rates of macroadenomas, MRI-visible microadenomas, and MRI-negative tumors were 66.7% (12/18), 89.3% (67/75), and 75% (15/20), respectively (p = 0.039). The surgical remission rates had a trend of improvement during the study period (87.5% in 2017-2018 vs 76.5% in 2014, p = 0.517). Multivariate regression analysis showed that a history of previous pituitary surgery (OR 0.300, 95% CI 0.100-0.903; p = 0.032) and MRI-visible microadenoma (OR 3.048, 95% CI 1.030-9.019; p = 0.044) were independent factors influencing surgical remission. The recurrence rate was 3.2% after a mean of 18 months after surgery. The remission rate of postoperative MDT management in patients with persistent disease was higher than non-MDT management (66.7% vs 0%, p = 0.033). In cases with preoperative BIPSS lateralization, 84.6% (44/52) were concordant with intraoperative findings. MRI-visible microadenoma and primary surgery were independent predictors of surgical remission in CD. The MDT management strategy helps to achieve a better overall outcome. BIPSS may help to lateralize the tumor in MRI-negative/equivocal microadenomas.

SAT-148 Ectopic ACTH Secretion Has Varied Presentation and Requires Individualized Treatment - One Size Does Not Fit All

Ectopic ACTH secretion (EAS) presents in myriad ways. We present five cases of EAS to highlight similarities and differences in presentation and treatment. The first woman with known metastatic lung neuroendocrine tumour (NET) for two years presented with facial fullness, proximal weakness, worsening hypertension and hypokalaemia. Random cortisol of 2742nmol/L (99.39mcg/dL), with adrenocorticotrophic hormone (ACTH) of 201ng/L (5-50), was in keeping with EAS. She received medical treatment followed by bilateral adrenalectomy with EAS resolution and development of adrenal insufficiency. She is doing well. The second woman with proximal weakness was evaluated by neurologists. All neurological tests were normal but facial fullness and easy bruising was noted. Random cortisol was 875nmol/L (31.71mcg/dL) and ACTH was 90 ng/L. Imaging revealed metastatic liver disease with unknown primary and biopsy confirmed NET. Cortisol rose despite medical treatment and she died within fifteen months. The third woman with significant smoking history presented with haemoptysis and breathlessness. A right lung mass was suspected on chest X-ray and confirmed with CT. Endobronchial ultrasound-guided biopsy revealed small cell lung cancer (SCLC). She developed generalised weakness and severe hypokalaemia. Random cortisol of 1645nmol/L (59.63mcg/dL) with ACTH of 282ng/L suggested EAS. Despite medical treatment, she died within two weeks. The fourth woman presented with confusion, hypertension and severe hypokalaemia. Morning cortisol of 8557nmol/L (310.19mcg/dL) and random ACTH of 73ng/L were suggestive of EAS. CT demonstrated left lung mass with widespread metastases. She deteriorated and died within 2 weeks. Our only man had incidentally discovered metastatic liver lesions on ultrasound. Further imaging revealed prostatic mass and biopsy showed small cell neuroendocrine cancer. He presented with severe hypokalaemia. Random cortisol was 1065nmol/L (38.61mcg/dL) and ACTH was 188ng/L. He was commenced on medical treatment but declined rapidly and died.All our patients had profound hypokalaemia and metastatic disease at presentation. Many patients do not exhibit classical cushingoid features as EAS tends to develop acutely and underlying malignancy drives weight loss. A high index of suspicion is required to make a diagnosis. EAS should be considered in patients with proximal myopathy, pigmentation, resistant or severe hypokalaemia or hypertension and known or suspected malignancy. Early and quick control of cortisol excess is essential to minimise cardiometabolic abnormalities, severe infections and thromboembolic complications. Prognosis depends upon age, frailty, comorbidity, nature of neoplasm and extent of hypercortisolaemia. Adrenolytics with or without bilateral adrenalectomy, reduction in tumour burden and management of complications are the mainstay of treatment.

OR23-01 Intrapatient ACTH Variability in Cushing’s Disease: Prognostic Significance

Introduction: In patients with Cushing’s Disease (CD), intrapatient variability of hormone measurements creates significant clinical challenges, therefore multiple measurements are recommended.1 Urinary and salivary cortisol variation has been well described. However, intrapatient variation of adrenocorticotropic hormone (ACTH) in CD remains unknown. In CD patients, ACTH levels are inherently elevated from baseline but the coefficient of diurnal variation is reduced.2Additionally, at each diurnal time point, these exists a significant variation around the mean for the ACTH levels. In this study, we first analyzed the intrapatient variablility of ACTH at each diurnal timepoint in patients with CD. CD is primarily a disorder of ACTH excess, and treatment directed at pituitary adenomas would presumably perturb ACTH levels prior to affecting serum or urine cortisol. We hypothesized that the coefficient of variation at each diurnal time-point can help predict remission from CD following surgery. Methods: We conducted a retrospective review of patients (n = 645) who had histopathologically confirmed diagnosis of CD from 2005-2019 (NCT NCT00060541). We selected patients that had ≥ 3 plasma ACTH values over a 7 day span prior to surgical or medical intervention. We grouped the ACTH measurements into morning (AM) and midnight (PM) values to account for diurnal variation in ACTH secretion. We then analyzed post-operative hormone measurements performed every 6 hours prior to administration of replacement corticosteroids. Remission was assigned to patients with nadir serum cortisol level ≤5 mcg/dL within ten days post-operatively3,4. Results: We found 54 patients with multiple PM (n = 27) and AM (n = 41) ACTH measurements within a 7 day span. We found that the median coefficient of variation (CV) of intra-patient variability was 19.7% (N=41) (95% CI:12.5-27.5) for the AM and was 24% (N=27) (95% CI: 9.6-31.8) for the PM. Age, the number of tests, or the length of test period were not correlated with CV or absolute levels of ACTH. The intraclass correlation coefficient (ICC) of the AM data set was 0.59 and the PM data set was 0.79 which demonstrates a good and excellent reliability respectively. We found that that, in general, 30-60% decrease from pre-operative ACTH levels predicted remission from CD. ACTH decrease >50% on POD2 and 3 had 100% specificity and sensitivity in predicting remission. The decrease in ACTH preceded cortisol nadir in 3/10 patients by 24 hours. Conclusion: We found significant intra-patient variability in plasma levels of ACTH at individual diurnal timepoints in CD patients. We also found that the change in ACTH >50% on POD2 or 3 is an excellent predictor of remission from CD.

Long-term outcomes of hypofractionated stereotactic radiotherapy for refractory functional pituitary adenoma

Refractory functional pituitary adenomas are often treated with single-session stereotactic radiosurgery (SRS) or conventionally fractionated intensity-modulated radiotherapy (IMRT). While single-fraction SRS offers convenience and short time to biochemical remission, large tumors with cranial nerve or chiasmatic involvement often preclude single-fraction SRS, and toxicity may be worse following single-fraction SRS compared with IMRT. The purpose of our study was to explore the long-term outcomes of a unique hypofractionated stereotactic radiotherapy (HSRT) regimen delivered in 2–5 fractions. After approval, we studied 16 consecutive patients treated with HSRT for refractory functional pituitary adenoma. Study endpoints included local control, biochemical control, and toxicity. Descriptive statistics summarized endpoints and clinicopathologic factors. Sixteen patients with adrenocorticotropic hormone secretion (n = 9, 56%), growth hormone secretion (n = 4, 25%), and prolactin secretion (n = 3, 19%) were studied with a median follow-up time after HSRT of 10 years (IQR 2–14 years). Patients were treated with two (n = 8), three (n = 1), or five (n = 7) fractions to median dose of 20.5 Gy (range 16–32 Gy). HSRT was well-tolerated with no acute side effects greater than CTCAE grade 1. Local control was 100%, and biochemical control at last follow-up was 58%. Over 142 years patient-years, no instances of optic neuropathy, secondary malignancy, malignant transformation, radionecrosis, cavernous sinus cranial neuropathy, or cerebrovascular complications were noted. HSRT for refractory pituitary adenoma is well-tolerated with long-term local and biochemical control comparable with single-fraction SRS or IMRT. Prospective studies should evaluate whether HSRT provides non-inferior biochemical control and improved toxicity compared with single-fraction SRS.

Ultra-high field magnetic resonance imaging for localization of corticotropin-secreting pituitary adenomas.

Cushing's disease manifests as symptoms of glucocorticoid excess secondary to the increased secretion of corticotropin by a corticotroph adenoma in the pituitary gland. Unfortunately, magnetic resonance imaging (MRI) performed at conventional clinical field strengths of 1.5 or 3 Tesla has limited sensitivity for the detection of these pituitary tumors, and radiologic uncertainty often necessitates more invasive workup to confirm diagnosis and guide resection. It has been postulated that higher static magnetic field strengths may increase the adenoma detection rate and thus the utility of MRI for this clinical application. In this report, we describe our initial experience using ultra-high field 7 Tesla (7T) MRI in patients with suspected Cushing's disease and negative or equivocal imaging at conventional field strengths. We performed contrast-enhanced 7T pituitary MRI in 10 patients with up to three different T1-weighted sequences and correlated the imaging abnormalities identified with results of histologic evaluation in patients who subsequently underwent resection. We found that 7T MRI enabled the identification of previously undetected areas of focal pituitary hypoenhancement in 9 patients (90%), of which 7 corresponded histologically to corticotroph adenomas. These early findings suggest an important adjunctive role for ultra-high field MR imaging in the noninvasive clinical workup of suspected Cushing's disease.

Nuclear Receptors as Regulators of Pituitary Corticotroph Pro-Opiomelanocortin Transcription.

The hypothalamic–pituitary–adrenal (HPA) axis plays a critical role in adaptive stress responses and maintaining organism homeostasis. The pituitary corticotroph is the central player in the HPA axis and is regulated by a plethora of hormonal and stress related factors that synergistically interact to activate and temper pro-opiomelanocortin (POMC) transcription, to either increase or decrease adrenocorticotropic hormone (ACTH) production and secretion as needed. Nuclear receptors are a family of highly conserved transcription factors that can also be induced by various physiologic signals, and they mediate their responses via multiple targets to regulate metabolism and homeostasis. In this review, we summarize the modulatory roles of nuclear receptors on pituitary corticotroph cell POMC transcription, describe the unique and complex role these factors play in hypothalamic–pituitary–adrenal axis (HPA) regulation and discuss potential therapeutic targets in disease states.

A rare cause of severe Cushing's syndrome.

SummaryEctopic adrenocorticotropic hormone (ACTH) production is an uncommon cause of Cushing’s syndrome and, rarely, the source can be a phaeochromocytoma. A 55-year-old man presented following an episode of presumed gastroenteritis with vomiting and general malaise. Further episodes of diarrhoea, joint pains and palpitations followed. On examination, he was hypertensive with no clinical features to suggest hypercortisolaemia. He was subsequently found to have raised plasma normetanephrines of 3.98 nmol/L (NR <0.71) and metanephrines of 0.69 nmol/L (NR <0.36). An adrenal CT showed a 3.8 cm right adrenal nodule, which was not MIBG-avid but was clinically and biochemically consistent with a phaeochromocytoma. He was started on alpha blockade and referred for right adrenalectomy. Four weeks later, on the day of admission for adrenalectomy, profound hypokalaemia was noted (serum potassium 2.0 mmol/L) with non-specific ST-segment ECG changes. He was also diagnosed with new-onset diabetes mellitus (capillary blood glucose of 28 mmol/L). He reported to have gained weight and his skin had become darker over the course of the last 4 weeks. Given these findings, he underwent overnight dexamethasone suppression testing, which showed a non-suppressed serum cortisol of 1099 nmol/L. Baseline serum ACTH was 273 ng/L. A preliminary diagnosis of ectopic ACTH secretion from the known right-sided phaeochromocytoma was made and he was started on metyrapone and insulin. Surgery was postponed for 4 weeks. Following uncomplicated laparoscopic adrenalectomy, the patient recovered with full resolution of symptoms.Learning points:Phaeochromocytomas are a rare source of ectopic ACTH secretion. A high clinical index of suspicion is therefore required to make the diagnosis.Ectopic ACTH secretion from a phaeochromocytoma can rapidly progress to severe Cushing’s syndrome, thus complicating tumour removal.Removal of the primary tumour often leads to full recovery.The limited literature suggests that the presence of ectopic Cushing’s syndrome does not appear to have any long-term prognostic implications.

The Neural Response of Deep Brain Structures to Odorant Stimulations: A Manganese-Enhanced MRI Study

An increased understanding of how odors are processed in the central nervous system may provide comprehensive information about the neural basis of odor-related behavior and learning. In this study, we investigated how different odors are processed from the olfactory bulb to the deep cerebral structures through various olfactory pathways. To do this, we employed a novel manganese-enhanced magnetic resonance imaging (MEMRI) method to map the activity-dependent functional connectivity of the olfactory and non-olfactory pathways associated with various odorants. Our MEMRI data revealed odor-specific neural pathways that correspond to different odorant stimulations, suggesting that different neural circuits may process different odorants. Among the odorants tested, formic acid, an alarm pheromone, stimulated not only the primary and secondary olfactory pathways but also the mesolimbic neural circuit, which overlaps with the dopaminergic neural pathway. Linalool, which is a major component of aroma oils, showed high Mn2+ uptake in the hypothalamus, which plays a role in the stress response through the secretion of corticotropin-releasing hormone (CRH), and consequently, the stimulation of corticotropin secretion. Acetone mainly activated the primary olfactory pathway, whereas saline acted as a non-odorous trigeminal stimulus. Taken together, our functional MEMRI using anatomic standardization and statistical analyses could be a promising in vivo imaging method to map neural connectivity, enabling further understanding of the neural processing of different odorants.

Cortisol levels after cold exposure are independent of adrenocorticotropic hormone stimulation.

We previously showed that postmortem serum levels of adrenocorticotropic hormone (ACTH) were significantly higher in cases of hypothermia (cold exposure) than other causes of death. This study examined how the human hypothalamic-pituitary-adrenal axis, and specifically cortisol, responds to hypothermia. Human samples: Autopsies on 205 subjects (147 men and 58 women; age 15–98 years, median 60 years) were performed within 3 days of death. Cause of death was classified as either hypothermia (cold exposure, n = 14) or non-cold exposure (controls; n = 191). Cortisol levels were determined in blood samples obtained from the left and right cardiac chambers and common iliac veins using a chemiluminescent enzyme immunoassay. Adrenal gland tissues samples were stained for cortisol using a rabbit anti-human polyclonal antibody. Cell culture: AtT20, a mouse ACTH secretory cell line, and Y-1, a corticosterone secretory cell line derived from a mouse adrenal tumor, were analyzed in mono-and co-culture, and times courses of ACTH (in AtT20) and corticosterone (in Y-1) secretion were assessed after low temperature exposure mimicking hypothermia and compared with data for samples collected postmortem for other cases of death. However, no correlation between ACTH concentration and cortisol levels was observed in hypothermia cases. Immunohistologic analyses of samples from hypothermia cases showed that cortisol staining was localized primarily to the nucleus rather than the cytoplasm of cells in the zona fasciculata of the adrenal gland. During both mono-culture and co-culture, AtT20 cells secreted high levels of ACTH after 10–15 minutes of cold exposure, whereas corticosterone secretion by Y-1 cells increased slowly during the first 15–20 minutes of cold exposure. Similar to autopsy results, no correlation was detected between ACTH levels and corticosterone secretion, either in mono-culture or co-culture experiments. These results suggested that ACTH-independent cortisol secretion may function as a stress response during cold exposure.

The correlation between the hypophysial gonadal axis with special reference to the role of fatty acids and isoenzyme during the ovarian maturation in female grass carp, Ctenopharyngodon idella

The present study was conducted to investigate the relationship between the gonad maturation of grass carp, Ctenopharyngodon idella and the changes of pituitary gland cells types coincides with oogonial development and their changes of fatty acid profile and isoenzyme electrophoresis. Five categories of oogenesis are detected such as immature, maturing, ripe spawning and follicular atresia. The pituitary gland has possessed six different kinds of cells. In the rostral pars distalis (RPD), two acidophilic cells types are distinguished; adrenocorticotropic hormone secreting cells (ACTH) and prolactin hormone secreting cells (PRL). The proximal pars distalis (PPD) exhibited two basophilic cell types include gonadotropic hormone secreting cells (GTH) and the thyrotrophic hormone secreting cells (TSH). During ripe stage, the gonadotrophic cells attained the highest changes of the GTH cells explained by increase of cytoplasmic secretory granules. The saturated fatty acids contents reached the maximum peak value and ranged from 38.45% to 39.19%. While unsaturated fatty acids (UFA) ranged from17.09.1% to17.49% and polyunsaturated fatty acids (PUFA) become 43.54% to 44.29%. The most abundant fatty acids were palmitic acid (C16:0), stearic acid (C18:0) in case of SFA, oleic acid (C18:1 n-9) in case of MUFA, linoleic (C18:2 n-6) in case of omega6 and docosahexaenoic (DHA) and acid (C22:6 n-3) Eicosapentaenoic (20:5n-3) (EPA) in case of omega3. The assayed isoenzymes electrophoresis was altered during the ovarian development. The authors finally concluded that there is a gradual change in the pituitary of endocrine cells parallel with changes of follicular development and assessed by alterations of isoenzyme electrophoresis and fatty acids content.

Pathological ATPergic Signaling in Major Depression and Bipolar Disorder.

The mood disorders, major depression (MD) and bipolar disorder (BD), have a high lifetime prevalence in the human population and accordingly generate huge costs for health care. Efficient, rapidly acting, and side-effect-free pharmaceuticals are hitherto not available, and therefore, the identification of new therapeutic targets is an imperative task for (pre)clinical research. Such a target may be the purinergic P2X7 receptor (P2X7R), which is localized in the central nervous system (CNS) at microglial and neuroglial cells mediating neuroinflammation. MD and BD are due to neuroinflammation caused in the first line by the release of the pro-inflammatory cytokine interleukin-1β (IL-1β) from the microglia. IL-1β in turn induces the secretion of corticotropin-releasing hormone (CRH) and in consequence the secretion of adrenocorticotropic hormone (ACTH) and cortisol, which together with a plethora of further cytokines/chemokines lead to mood disorders. A number of biochemical/molecular biological measurements including the use of P2X7R- or IL-1β-deficient mice confirmed this chain of events. More recent studies showed that a decrease in the astrocytic release of ATP in the prefrontal cortex and hippocampus is a major cause of mood disorders. It is an attractive hypothesis that compensatory increases in P2X7Rs in these areas of the brain are the immediate actuators of MD and BD. Hence, blood-brain barrier-permeable P2X7R antagonists may be promising therapeutic tools to improve depressive disorders in humans.

Molecular Basis for Hormone Recognition and Activation of Corticotropin-Releasing Factor Receptors.

Corticotropin-releasing factor (CRF) and the three related peptides urocortins 1-3 (UCN1-UCN3) are endocrine hormones that control the stress responses by activating CRF1R and CRF2R, two members of class B G-protein-coupled receptors (GPCRs). Here, we present two cryoelectron microscopy (cryo-EM) structures of UCN1-bound CRF1R and CRF2R with the stimulatory G protein. In both structures, UCN1 adopts a single straight helix with its N terminus dipped into the receptor transmembrane bundle. Although the peptide-binding residues in CRF1R and CRF2R are different from other members of class B GPCRs, the residues involved in receptor activation and G protein coupling are conserved. In addition, both structures reveal bound cholesterol molecules to the receptor transmembrane helices. Our structures define the basis of ligand-binding specificity in the CRF receptor-hormone system, establish a common mechanism of class B GPCR activation and G protein coupling, and provide a paradigm for studying membrane protein-lipid interactions for class B GPCRs.

Pharmacological evaluation of a novel corticotropin‐releasing factor 1 receptor antagonist T‐3047928 in stress‐induced animal models in a comparison with alosetron

The major symptoms of irritable bowel syndrome (IBS) are changes in bowel habits and abdominal pain. Psychological stress is the major pathophysiological components of IBS. Corticotropin-releasing factor (CRF) is a well-known integrator in response to psychological stress. In this study, a novel CRF1 receptor antagonist T-3047928 was evaluated in stress-induced IBS models of rats to explore its potency for IBS. Plasma adrenocorticotropic hormone (ACTH) levels after intravenous oCRH challenge were measured as a pharmacodynamic marker. Efficacies of oral T-3047928 were compared with oral alosetron, a 5-HT3 antagonist, on conditioning fear stress (CFS)-induced defecation, restraint stress (RS)-induced acute visceral pain, specific alteration of rhythm in temperature (SART) stress-induced chronic visceral pain, and normal defecation. T-3047928 (1-10mg/kg, p.o.) demonstrated a dose-dependent inhibition on oCRH-induced ACTH secretion. In disease models, T-3047928 suppressed fecal pellet output induced by CFS and improved both acute and chronic visceral hypersensitivity induced by RS and SART stress, respectively. Alosetron was also efficacious in stress-induced defecation and visceral pain models at 1 and 10mg/kg, respectively. Alosetron, however, also suppressed normal defecation at lower those. On the other hand, T-3047928 did not change normal defecation even at higher dose than those in disease models. T-3047928 is an orally active CRF1 antagonist that demonstrated potent inhibitory effects in stress-associated IBS models with no effect on normal defecation. Therefore, it is suggested that T-3047928 may have a potency as a novel option for IBS-D therapy with minimal constipation risk.

Effects of epigenetic pathway inhibitors on corticotroph tumour AtT20 cells.

Medical treatments for corticotrophinomas are limited, and we therefore investigated the effects of epigenetic modulators, a new class of anti-tumour drugs, on the murine adrenocorticotropic hormone (ACTH)-secreting corticotrophinoma cell line AtT20. We found that AtT20 cells express members of the bromo and extra-terminal (BET) protein family, which bind acetylated histones, and therefore, studied the anti-proliferative and pro-apoptotic effects of two BET inhibitors, referred to as (+)-JQ1 (JQ1) and PFI-1, using CellTiter Blue and Caspase Glo assays, respectively. JQ1 and PFI-1 significantly decreased proliferation by 95% (P < 0.0005) and 43% (P < 0.0005), respectively, but only JQ1 significantly increased apoptosis by >50-fold (P < 0.0005), when compared to untreated control cells. The anti-proliferative effects of JQ1 and PFI-1 remained for 96 h after removal of the respective compound. JQ1, but not PFI-1, affected the cell cycle, as assessed by propidium iodide staining and flow cytometry, and resulted in a higher number of AtT20 cells in the sub G1 phase. RNA-sequence analysis, which was confirmed by qRT-PCR and Western blot analyses, revealed that JQ1 treatment significantly altered expression of genes involved in apoptosis, such as NFκB, and the somatostatin receptor 2 (SSTR2) anti-proliferative signalling pathway, including SSTR2. JQ1 treatment also significantly reduced transcription and protein expression of the ACTH precursor pro-opiomelanocortin (POMC) and ACTH secretion by AtT20 cells. Thus, JQ1 treatment has anti-proliferative and pro-apoptotic effects on AtT20 cells and reduces ACTH secretion, thereby indicating that BET inhibition may provide a novel approach for treatment of corticotrophinomas.

Hypothalamic Contribution to Pituitary Functions Is Recapitulated In Vitro Using 3D-Cultured Human iPS Cells

The pituitary is a major hormone center that secretes systemic hormones responding to hypothalamus-derived-releasing hormones. Previously, we reported the independent pituitary induction and hypothalamic differentiation of human embryonic stem cells (ESCs). Here, a functional hypothalamic-pituitary unit is generated using human induced pluripotent stem (iPS) cells invitro. The adrenocorticotropic hormone (ACTH) secretion capacity of the induced pituitary reached a comparable level to that of adult mouse pituitary because of the simultaneous maturation with hypothalamic neurons within the same aggregates. Corticotropin-releasing hormone (CRH) from the hypothalamic area regulates ACTH cells similarly to our hypothalamic-pituitary axis. Our induced hypothalamic-pituitary units respond to environmental hypoglycemic condition invitro, which mimics a life-threatening situation invivo, through the CRH-ACTH pathway, and succeed in increasing ACTH secretion. Thus, we generated powerful hybrid organoids by recapitulating hypothalamic-pituitary development, showing autonomous maturation on the basis of interactions between developing tissues.

Adrenal Insufficiency due to Total Primary Empty Sella Syndrome

A 64-year-old woman was transported suffering from persistent lower abdominal pain, vomiting, and low-grade fever. Magnetic resonance imaging revealed an empty sella (ES) and hormone tests revealed a disappearance of diurnal variation of cortisol, low cortisol and adrenocorticotropic hormone (ACTH) secretion especially in the morning, and poor ACTH-cortisol axis reaction, as well as normal hypothalamus-pituitary gland-thyroid or adrenal gland axis hormone reaction. The cause of ES remained unclear; however, based on a diagnosis as adrenal insufficiency due to inappropriate ACTH secretion caused by total primary ES syndrome, we started hydrocortisone (15 mg/day). Afterwards, she immediately became symptom-free and was discharged. J Endocrinol Metab. 2020;10(5):144-153 doi: https://doi.org/10.14740/jem686